2isqrt (example 3.6)

Percentage Accurate: 38.6% → 99.6%
Time: 5.8s
Alternatives: 12
Speedup: 1.5×

Specification

?
\[x > 1 \land x < 10^{+308}\]
\[\begin{array}{l} \\ \frac{1}{\sqrt{x}} - \frac{1}{\sqrt{x + 1}} \end{array} \]
(FPCore (x) :precision binary64 (- (/ 1.0 (sqrt x)) (/ 1.0 (sqrt (+ x 1.0)))))
double code(double x) {
	return (1.0 / sqrt(x)) - (1.0 / sqrt((x + 1.0)));
}
real(8) function code(x)
    real(8), intent (in) :: x
    code = (1.0d0 / sqrt(x)) - (1.0d0 / sqrt((x + 1.0d0)))
end function
public static double code(double x) {
	return (1.0 / Math.sqrt(x)) - (1.0 / Math.sqrt((x + 1.0)));
}
def code(x):
	return (1.0 / math.sqrt(x)) - (1.0 / math.sqrt((x + 1.0)))
function code(x)
	return Float64(Float64(1.0 / sqrt(x)) - Float64(1.0 / sqrt(Float64(x + 1.0))))
end
function tmp = code(x)
	tmp = (1.0 / sqrt(x)) - (1.0 / sqrt((x + 1.0)));
end
code[x_] := N[(N[(1.0 / N[Sqrt[x], $MachinePrecision]), $MachinePrecision] - N[(1.0 / N[Sqrt[N[(x + 1.0), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\frac{1}{\sqrt{x}} - \frac{1}{\sqrt{x + 1}}
\end{array}

Sampling outcomes in binary64 precision:

Local Percentage Accuracy vs ?

The average percentage accuracy by input value. Horizontal axis shows value of an input variable; the variable is choosen in the title. Vertical axis is accuracy; higher is better. Red represent the original program, while blue represents Herbie's suggestion. These can be toggled with buttons below the plot. The line is an average while dots represent individual samples.

Accuracy vs Speed?

Herbie found 12 alternatives:

AlternativeAccuracySpeedup
The accuracy (vertical axis) and speed (horizontal axis) of each alternatives. Up and to the right is better. The red square shows the initial program, and each blue circle shows an alternative.The line shows the best available speed-accuracy tradeoffs.

Initial Program: 38.6% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \frac{1}{\sqrt{x}} - \frac{1}{\sqrt{x + 1}} \end{array} \]
(FPCore (x) :precision binary64 (- (/ 1.0 (sqrt x)) (/ 1.0 (sqrt (+ x 1.0)))))
double code(double x) {
	return (1.0 / sqrt(x)) - (1.0 / sqrt((x + 1.0)));
}
real(8) function code(x)
    real(8), intent (in) :: x
    code = (1.0d0 / sqrt(x)) - (1.0d0 / sqrt((x + 1.0d0)))
end function
public static double code(double x) {
	return (1.0 / Math.sqrt(x)) - (1.0 / Math.sqrt((x + 1.0)));
}
def code(x):
	return (1.0 / math.sqrt(x)) - (1.0 / math.sqrt((x + 1.0)))
function code(x)
	return Float64(Float64(1.0 / sqrt(x)) - Float64(1.0 / sqrt(Float64(x + 1.0))))
end
function tmp = code(x)
	tmp = (1.0 / sqrt(x)) - (1.0 / sqrt((x + 1.0)));
end
code[x_] := N[(N[(1.0 / N[Sqrt[x], $MachinePrecision]), $MachinePrecision] - N[(1.0 / N[Sqrt[N[(x + 1.0), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\frac{1}{\sqrt{x}} - \frac{1}{\sqrt{x + 1}}
\end{array}

Alternative 1: 99.6% accurate, 0.3× speedup?

\[\begin{array}{l} \\ \frac{\frac{1}{\mathsf{hypot}\left(\sqrt{x}, x\right) + x}}{\sqrt{1 + x}} \end{array} \]
(FPCore (x)
 :precision binary64
 (/ (/ 1.0 (+ (hypot (sqrt x) x) x)) (sqrt (+ 1.0 x))))
double code(double x) {
	return (1.0 / (hypot(sqrt(x), x) + x)) / sqrt((1.0 + x));
}
public static double code(double x) {
	return (1.0 / (Math.hypot(Math.sqrt(x), x) + x)) / Math.sqrt((1.0 + x));
}
def code(x):
	return (1.0 / (math.hypot(math.sqrt(x), x) + x)) / math.sqrt((1.0 + x))
function code(x)
	return Float64(Float64(1.0 / Float64(hypot(sqrt(x), x) + x)) / sqrt(Float64(1.0 + x)))
end
function tmp = code(x)
	tmp = (1.0 / (hypot(sqrt(x), x) + x)) / sqrt((1.0 + x));
end
code[x_] := N[(N[(1.0 / N[(N[Sqrt[N[Sqrt[x], $MachinePrecision] ^ 2 + x ^ 2], $MachinePrecision] + x), $MachinePrecision]), $MachinePrecision] / N[Sqrt[N[(1.0 + x), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\frac{\frac{1}{\mathsf{hypot}\left(\sqrt{x}, x\right) + x}}{\sqrt{1 + x}}
\end{array}
Derivation
  1. Initial program 39.1%

    \[\frac{1}{\sqrt{x}} - \frac{1}{\sqrt{x + 1}} \]
  2. Add Preprocessing
  3. Step-by-step derivation
    1. lift--.f64N/A

      \[\leadsto \color{blue}{\frac{1}{\sqrt{x}} - \frac{1}{\sqrt{x + 1}}} \]
    2. lift-/.f64N/A

      \[\leadsto \color{blue}{\frac{1}{\sqrt{x}}} - \frac{1}{\sqrt{x + 1}} \]
    3. lift-/.f64N/A

      \[\leadsto \frac{1}{\sqrt{x}} - \color{blue}{\frac{1}{\sqrt{x + 1}}} \]
    4. frac-subN/A

      \[\leadsto \color{blue}{\frac{1 \cdot \sqrt{x + 1} - \sqrt{x} \cdot 1}{\sqrt{x} \cdot \sqrt{x + 1}}} \]
    5. div-invN/A

      \[\leadsto \color{blue}{\left(1 \cdot \sqrt{x + 1} - \sqrt{x} \cdot 1\right) \cdot \frac{1}{\sqrt{x} \cdot \sqrt{x + 1}}} \]
    6. metadata-evalN/A

      \[\leadsto \left(1 \cdot \sqrt{x + 1} - \sqrt{x} \cdot \color{blue}{\frac{1}{1}}\right) \cdot \frac{1}{\sqrt{x} \cdot \sqrt{x + 1}} \]
    7. div-invN/A

      \[\leadsto \left(1 \cdot \sqrt{x + 1} - \color{blue}{\frac{\sqrt{x}}{1}}\right) \cdot \frac{1}{\sqrt{x} \cdot \sqrt{x + 1}} \]
    8. *-lft-identityN/A

      \[\leadsto \left(\color{blue}{\sqrt{x + 1}} - \frac{\sqrt{x}}{1}\right) \cdot \frac{1}{\sqrt{x} \cdot \sqrt{x + 1}} \]
    9. flip--N/A

      \[\leadsto \color{blue}{\frac{\sqrt{x + 1} \cdot \sqrt{x + 1} - \frac{\sqrt{x}}{1} \cdot \frac{\sqrt{x}}{1}}{\sqrt{x + 1} + \frac{\sqrt{x}}{1}}} \cdot \frac{1}{\sqrt{x} \cdot \sqrt{x + 1}} \]
    10. metadata-evalN/A

      \[\leadsto \frac{\sqrt{x + 1} \cdot \sqrt{x + 1} - \frac{\sqrt{x}}{1} \cdot \frac{\sqrt{x}}{1}}{\sqrt{x + 1} + \frac{\sqrt{x}}{1}} \cdot \frac{\color{blue}{1 \cdot 1}}{\sqrt{x} \cdot \sqrt{x + 1}} \]
    11. frac-timesN/A

      \[\leadsto \frac{\sqrt{x + 1} \cdot \sqrt{x + 1} - \frac{\sqrt{x}}{1} \cdot \frac{\sqrt{x}}{1}}{\sqrt{x + 1} + \frac{\sqrt{x}}{1}} \cdot \color{blue}{\left(\frac{1}{\sqrt{x}} \cdot \frac{1}{\sqrt{x + 1}}\right)} \]
    12. lift-/.f64N/A

      \[\leadsto \frac{\sqrt{x + 1} \cdot \sqrt{x + 1} - \frac{\sqrt{x}}{1} \cdot \frac{\sqrt{x}}{1}}{\sqrt{x + 1} + \frac{\sqrt{x}}{1}} \cdot \left(\color{blue}{\frac{1}{\sqrt{x}}} \cdot \frac{1}{\sqrt{x + 1}}\right) \]
    13. frac-2negN/A

      \[\leadsto \frac{\sqrt{x + 1} \cdot \sqrt{x + 1} - \frac{\sqrt{x}}{1} \cdot \frac{\sqrt{x}}{1}}{\sqrt{x + 1} + \frac{\sqrt{x}}{1}} \cdot \left(\frac{1}{\sqrt{x}} \cdot \color{blue}{\frac{\mathsf{neg}\left(1\right)}{\mathsf{neg}\left(\sqrt{x + 1}\right)}}\right) \]
    14. metadata-evalN/A

      \[\leadsto \frac{\sqrt{x + 1} \cdot \sqrt{x + 1} - \frac{\sqrt{x}}{1} \cdot \frac{\sqrt{x}}{1}}{\sqrt{x + 1} + \frac{\sqrt{x}}{1}} \cdot \left(\frac{1}{\sqrt{x}} \cdot \frac{\color{blue}{-1}}{\mathsf{neg}\left(\sqrt{x + 1}\right)}\right) \]
    15. associate-*r/N/A

      \[\leadsto \frac{\sqrt{x + 1} \cdot \sqrt{x + 1} - \frac{\sqrt{x}}{1} \cdot \frac{\sqrt{x}}{1}}{\sqrt{x + 1} + \frac{\sqrt{x}}{1}} \cdot \color{blue}{\frac{\frac{1}{\sqrt{x}} \cdot -1}{\mathsf{neg}\left(\sqrt{x + 1}\right)}} \]
  4. Applied rewrites41.1%

    \[\leadsto \color{blue}{\frac{\left(\left(x + 1\right) - x\right) \cdot \frac{-1}{\sqrt{x}}}{\left(\sqrt{x} + \sqrt{x + 1}\right) \cdot \left(-\sqrt{x + 1}\right)}} \]
  5. Taylor expanded in x around 0

    \[\leadsto \frac{\color{blue}{1} \cdot \frac{-1}{\sqrt{x}}}{\left(\sqrt{x} + \sqrt{x + 1}\right) \cdot \left(-\sqrt{x + 1}\right)} \]
  6. Step-by-step derivation
    1. Applied rewrites99.3%

      \[\leadsto \frac{\color{blue}{1} \cdot \frac{-1}{\sqrt{x}}}{\left(\sqrt{x} + \sqrt{x + 1}\right) \cdot \left(-\sqrt{x + 1}\right)} \]
    2. Step-by-step derivation
      1. lift-/.f64N/A

        \[\leadsto \color{blue}{\frac{1 \cdot \frac{-1}{\sqrt{x}}}{\left(\sqrt{x} + \sqrt{x + 1}\right) \cdot \left(-\sqrt{x + 1}\right)}} \]
      2. lift-*.f64N/A

        \[\leadsto \frac{1 \cdot \frac{-1}{\sqrt{x}}}{\color{blue}{\left(\sqrt{x} + \sqrt{x + 1}\right) \cdot \left(-\sqrt{x + 1}\right)}} \]
      3. associate-/r*N/A

        \[\leadsto \color{blue}{\frac{\frac{1 \cdot \frac{-1}{\sqrt{x}}}{\sqrt{x} + \sqrt{x + 1}}}{-\sqrt{x + 1}}} \]
      4. lower-/.f64N/A

        \[\leadsto \color{blue}{\frac{\frac{1 \cdot \frac{-1}{\sqrt{x}}}{\sqrt{x} + \sqrt{x + 1}}}{-\sqrt{x + 1}}} \]
    3. Applied rewrites99.7%

      \[\leadsto \color{blue}{\frac{\frac{1 \cdot -1}{\mathsf{hypot}\left(\sqrt{x}, x\right) + x}}{-\sqrt{1 + x}}} \]
    4. Final simplification99.7%

      \[\leadsto \frac{\frac{1}{\mathsf{hypot}\left(\sqrt{x}, x\right) + x}}{\sqrt{1 + x}} \]
    5. Add Preprocessing

    Alternative 2: 99.6% accurate, 0.6× speedup?

    \[\begin{array}{l} \\ \begin{array}{l} t_0 := \sqrt{1 + x}\\ \frac{\frac{1}{\frac{x}{\sqrt{x}}}}{\left(t\_0 + \sqrt{x}\right) \cdot t\_0} \end{array} \end{array} \]
    (FPCore (x)
     :precision binary64
     (let* ((t_0 (sqrt (+ 1.0 x))))
       (/ (/ 1.0 (/ x (sqrt x))) (* (+ t_0 (sqrt x)) t_0))))
    double code(double x) {
    	double t_0 = sqrt((1.0 + x));
    	return (1.0 / (x / sqrt(x))) / ((t_0 + sqrt(x)) * t_0);
    }
    
    real(8) function code(x)
        real(8), intent (in) :: x
        real(8) :: t_0
        t_0 = sqrt((1.0d0 + x))
        code = (1.0d0 / (x / sqrt(x))) / ((t_0 + sqrt(x)) * t_0)
    end function
    
    public static double code(double x) {
    	double t_0 = Math.sqrt((1.0 + x));
    	return (1.0 / (x / Math.sqrt(x))) / ((t_0 + Math.sqrt(x)) * t_0);
    }
    
    def code(x):
    	t_0 = math.sqrt((1.0 + x))
    	return (1.0 / (x / math.sqrt(x))) / ((t_0 + math.sqrt(x)) * t_0)
    
    function code(x)
    	t_0 = sqrt(Float64(1.0 + x))
    	return Float64(Float64(1.0 / Float64(x / sqrt(x))) / Float64(Float64(t_0 + sqrt(x)) * t_0))
    end
    
    function tmp = code(x)
    	t_0 = sqrt((1.0 + x));
    	tmp = (1.0 / (x / sqrt(x))) / ((t_0 + sqrt(x)) * t_0);
    end
    
    code[x_] := Block[{t$95$0 = N[Sqrt[N[(1.0 + x), $MachinePrecision]], $MachinePrecision]}, N[(N[(1.0 / N[(x / N[Sqrt[x], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / N[(N[(t$95$0 + N[Sqrt[x], $MachinePrecision]), $MachinePrecision] * t$95$0), $MachinePrecision]), $MachinePrecision]]
    
    \begin{array}{l}
    
    \\
    \begin{array}{l}
    t_0 := \sqrt{1 + x}\\
    \frac{\frac{1}{\frac{x}{\sqrt{x}}}}{\left(t\_0 + \sqrt{x}\right) \cdot t\_0}
    \end{array}
    \end{array}
    
    Derivation
    1. Initial program 39.1%

      \[\frac{1}{\sqrt{x}} - \frac{1}{\sqrt{x + 1}} \]
    2. Add Preprocessing
    3. Step-by-step derivation
      1. lift--.f64N/A

        \[\leadsto \color{blue}{\frac{1}{\sqrt{x}} - \frac{1}{\sqrt{x + 1}}} \]
      2. lift-/.f64N/A

        \[\leadsto \color{blue}{\frac{1}{\sqrt{x}}} - \frac{1}{\sqrt{x + 1}} \]
      3. lift-/.f64N/A

        \[\leadsto \frac{1}{\sqrt{x}} - \color{blue}{\frac{1}{\sqrt{x + 1}}} \]
      4. frac-subN/A

        \[\leadsto \color{blue}{\frac{1 \cdot \sqrt{x + 1} - \sqrt{x} \cdot 1}{\sqrt{x} \cdot \sqrt{x + 1}}} \]
      5. div-invN/A

        \[\leadsto \color{blue}{\left(1 \cdot \sqrt{x + 1} - \sqrt{x} \cdot 1\right) \cdot \frac{1}{\sqrt{x} \cdot \sqrt{x + 1}}} \]
      6. metadata-evalN/A

        \[\leadsto \left(1 \cdot \sqrt{x + 1} - \sqrt{x} \cdot \color{blue}{\frac{1}{1}}\right) \cdot \frac{1}{\sqrt{x} \cdot \sqrt{x + 1}} \]
      7. div-invN/A

        \[\leadsto \left(1 \cdot \sqrt{x + 1} - \color{blue}{\frac{\sqrt{x}}{1}}\right) \cdot \frac{1}{\sqrt{x} \cdot \sqrt{x + 1}} \]
      8. *-lft-identityN/A

        \[\leadsto \left(\color{blue}{\sqrt{x + 1}} - \frac{\sqrt{x}}{1}\right) \cdot \frac{1}{\sqrt{x} \cdot \sqrt{x + 1}} \]
      9. flip--N/A

        \[\leadsto \color{blue}{\frac{\sqrt{x + 1} \cdot \sqrt{x + 1} - \frac{\sqrt{x}}{1} \cdot \frac{\sqrt{x}}{1}}{\sqrt{x + 1} + \frac{\sqrt{x}}{1}}} \cdot \frac{1}{\sqrt{x} \cdot \sqrt{x + 1}} \]
      10. metadata-evalN/A

        \[\leadsto \frac{\sqrt{x + 1} \cdot \sqrt{x + 1} - \frac{\sqrt{x}}{1} \cdot \frac{\sqrt{x}}{1}}{\sqrt{x + 1} + \frac{\sqrt{x}}{1}} \cdot \frac{\color{blue}{1 \cdot 1}}{\sqrt{x} \cdot \sqrt{x + 1}} \]
      11. frac-timesN/A

        \[\leadsto \frac{\sqrt{x + 1} \cdot \sqrt{x + 1} - \frac{\sqrt{x}}{1} \cdot \frac{\sqrt{x}}{1}}{\sqrt{x + 1} + \frac{\sqrt{x}}{1}} \cdot \color{blue}{\left(\frac{1}{\sqrt{x}} \cdot \frac{1}{\sqrt{x + 1}}\right)} \]
      12. lift-/.f64N/A

        \[\leadsto \frac{\sqrt{x + 1} \cdot \sqrt{x + 1} - \frac{\sqrt{x}}{1} \cdot \frac{\sqrt{x}}{1}}{\sqrt{x + 1} + \frac{\sqrt{x}}{1}} \cdot \left(\color{blue}{\frac{1}{\sqrt{x}}} \cdot \frac{1}{\sqrt{x + 1}}\right) \]
      13. frac-2negN/A

        \[\leadsto \frac{\sqrt{x + 1} \cdot \sqrt{x + 1} - \frac{\sqrt{x}}{1} \cdot \frac{\sqrt{x}}{1}}{\sqrt{x + 1} + \frac{\sqrt{x}}{1}} \cdot \left(\frac{1}{\sqrt{x}} \cdot \color{blue}{\frac{\mathsf{neg}\left(1\right)}{\mathsf{neg}\left(\sqrt{x + 1}\right)}}\right) \]
      14. metadata-evalN/A

        \[\leadsto \frac{\sqrt{x + 1} \cdot \sqrt{x + 1} - \frac{\sqrt{x}}{1} \cdot \frac{\sqrt{x}}{1}}{\sqrt{x + 1} + \frac{\sqrt{x}}{1}} \cdot \left(\frac{1}{\sqrt{x}} \cdot \frac{\color{blue}{-1}}{\mathsf{neg}\left(\sqrt{x + 1}\right)}\right) \]
      15. associate-*r/N/A

        \[\leadsto \frac{\sqrt{x + 1} \cdot \sqrt{x + 1} - \frac{\sqrt{x}}{1} \cdot \frac{\sqrt{x}}{1}}{\sqrt{x + 1} + \frac{\sqrt{x}}{1}} \cdot \color{blue}{\frac{\frac{1}{\sqrt{x}} \cdot -1}{\mathsf{neg}\left(\sqrt{x + 1}\right)}} \]
    4. Applied rewrites41.1%

      \[\leadsto \color{blue}{\frac{\left(\left(x + 1\right) - x\right) \cdot \frac{-1}{\sqrt{x}}}{\left(\sqrt{x} + \sqrt{x + 1}\right) \cdot \left(-\sqrt{x + 1}\right)}} \]
    5. Taylor expanded in x around 0

      \[\leadsto \frac{\color{blue}{1} \cdot \frac{-1}{\sqrt{x}}}{\left(\sqrt{x} + \sqrt{x + 1}\right) \cdot \left(-\sqrt{x + 1}\right)} \]
    6. Step-by-step derivation
      1. Applied rewrites99.3%

        \[\leadsto \frac{\color{blue}{1} \cdot \frac{-1}{\sqrt{x}}}{\left(\sqrt{x} + \sqrt{x + 1}\right) \cdot \left(-\sqrt{x + 1}\right)} \]
      2. Step-by-step derivation
        1. lift-*.f64N/A

          \[\leadsto \frac{\color{blue}{1 \cdot \frac{-1}{\sqrt{x}}}}{\left(\sqrt{x} + \sqrt{x + 1}\right) \cdot \left(-\sqrt{x + 1}\right)} \]
        2. lift-/.f64N/A

          \[\leadsto \frac{1 \cdot \color{blue}{\frac{-1}{\sqrt{x}}}}{\left(\sqrt{x} + \sqrt{x + 1}\right) \cdot \left(-\sqrt{x + 1}\right)} \]
        3. frac-2negN/A

          \[\leadsto \frac{1 \cdot \color{blue}{\frac{\mathsf{neg}\left(-1\right)}{\mathsf{neg}\left(\sqrt{x}\right)}}}{\left(\sqrt{x} + \sqrt{x + 1}\right) \cdot \left(-\sqrt{x + 1}\right)} \]
        4. metadata-evalN/A

          \[\leadsto \frac{1 \cdot \frac{\color{blue}{1}}{\mathsf{neg}\left(\sqrt{x}\right)}}{\left(\sqrt{x} + \sqrt{x + 1}\right) \cdot \left(-\sqrt{x + 1}\right)} \]
        5. un-div-invN/A

          \[\leadsto \frac{\color{blue}{\frac{1}{\mathsf{neg}\left(\sqrt{x}\right)}}}{\left(\sqrt{x} + \sqrt{x + 1}\right) \cdot \left(-\sqrt{x + 1}\right)} \]
        6. lower-/.f64N/A

          \[\leadsto \frac{\color{blue}{\frac{1}{\mathsf{neg}\left(\sqrt{x}\right)}}}{\left(\sqrt{x} + \sqrt{x + 1}\right) \cdot \left(-\sqrt{x + 1}\right)} \]
        7. lower-neg.f6499.3

          \[\leadsto \frac{\frac{1}{\color{blue}{-\sqrt{x}}}}{\left(\sqrt{x} + \sqrt{x + 1}\right) \cdot \left(-\sqrt{x + 1}\right)} \]
        8. lift-*.f64N/A

          \[\leadsto \frac{\frac{1}{-\sqrt{x}}}{\color{blue}{\left(\sqrt{x} + \sqrt{x + 1}\right) \cdot \left(-\sqrt{x + 1}\right)}} \]
        9. *-commutativeN/A

          \[\leadsto \frac{\frac{1}{-\sqrt{x}}}{\color{blue}{\left(-\sqrt{x + 1}\right) \cdot \left(\sqrt{x} + \sqrt{x + 1}\right)}} \]
        10. lower-*.f6499.3

          \[\leadsto \frac{\frac{1}{-\sqrt{x}}}{\color{blue}{\left(-\sqrt{x + 1}\right) \cdot \left(\sqrt{x} + \sqrt{x + 1}\right)}} \]
        11. lift-+.f64N/A

          \[\leadsto \frac{\frac{1}{-\sqrt{x}}}{\left(-\sqrt{\color{blue}{x + 1}}\right) \cdot \left(\sqrt{x} + \sqrt{x + 1}\right)} \]
        12. +-commutativeN/A

          \[\leadsto \frac{\frac{1}{-\sqrt{x}}}{\left(-\sqrt{\color{blue}{1 + x}}\right) \cdot \left(\sqrt{x} + \sqrt{x + 1}\right)} \]
        13. lower-+.f6499.3

          \[\leadsto \frac{\frac{1}{-\sqrt{x}}}{\left(-\sqrt{\color{blue}{1 + x}}\right) \cdot \left(\sqrt{x} + \sqrt{x + 1}\right)} \]
        14. lift-+.f64N/A

          \[\leadsto \frac{\frac{1}{-\sqrt{x}}}{\left(-\sqrt{1 + x}\right) \cdot \color{blue}{\left(\sqrt{x} + \sqrt{x + 1}\right)}} \]
        15. +-commutativeN/A

          \[\leadsto \frac{\frac{1}{-\sqrt{x}}}{\left(-\sqrt{1 + x}\right) \cdot \color{blue}{\left(\sqrt{x + 1} + \sqrt{x}\right)}} \]
        16. lower-+.f6499.3

          \[\leadsto \frac{\frac{1}{-\sqrt{x}}}{\left(-\sqrt{1 + x}\right) \cdot \color{blue}{\left(\sqrt{x + 1} + \sqrt{x}\right)}} \]
        17. lift-+.f64N/A

          \[\leadsto \frac{\frac{1}{-\sqrt{x}}}{\left(-\sqrt{1 + x}\right) \cdot \left(\sqrt{\color{blue}{x + 1}} + \sqrt{x}\right)} \]
        18. +-commutativeN/A

          \[\leadsto \frac{\frac{1}{-\sqrt{x}}}{\left(-\sqrt{1 + x}\right) \cdot \left(\sqrt{\color{blue}{1 + x}} + \sqrt{x}\right)} \]
        19. lower-+.f6499.3

          \[\leadsto \frac{\frac{1}{-\sqrt{x}}}{\left(-\sqrt{1 + x}\right) \cdot \left(\sqrt{\color{blue}{1 + x}} + \sqrt{x}\right)} \]
      3. Applied rewrites99.3%

        \[\leadsto \color{blue}{\frac{\frac{1}{-\sqrt{x}}}{\left(-\sqrt{1 + x}\right) \cdot \left(\sqrt{1 + x} + \sqrt{x}\right)}} \]
      4. Step-by-step derivation
        1. unpow1N/A

          \[\leadsto \frac{\frac{1}{-\color{blue}{{\left(\sqrt{x}\right)}^{1}}}}{\left(-\sqrt{1 + x}\right) \cdot \left(\sqrt{1 + x} + \sqrt{x}\right)} \]
        2. metadata-evalN/A

          \[\leadsto \frac{\frac{1}{-{\left(\sqrt{x}\right)}^{\color{blue}{\left(2 + -1\right)}}}}{\left(-\sqrt{1 + x}\right) \cdot \left(\sqrt{1 + x} + \sqrt{x}\right)} \]
        3. pow-prod-upN/A

          \[\leadsto \frac{\frac{1}{-\color{blue}{{\left(\sqrt{x}\right)}^{2} \cdot {\left(\sqrt{x}\right)}^{-1}}}}{\left(-\sqrt{1 + x}\right) \cdot \left(\sqrt{1 + x} + \sqrt{x}\right)} \]
        4. pow2N/A

          \[\leadsto \frac{\frac{1}{-\color{blue}{\left(\sqrt{x} \cdot \sqrt{x}\right)} \cdot {\left(\sqrt{x}\right)}^{-1}}}{\left(-\sqrt{1 + x}\right) \cdot \left(\sqrt{1 + x} + \sqrt{x}\right)} \]
        5. lift-sqrt.f64N/A

          \[\leadsto \frac{\frac{1}{-\left(\color{blue}{\sqrt{x}} \cdot \sqrt{x}\right) \cdot {\left(\sqrt{x}\right)}^{-1}}}{\left(-\sqrt{1 + x}\right) \cdot \left(\sqrt{1 + x} + \sqrt{x}\right)} \]
        6. lift-sqrt.f64N/A

          \[\leadsto \frac{\frac{1}{-\left(\sqrt{x} \cdot \color{blue}{\sqrt{x}}\right) \cdot {\left(\sqrt{x}\right)}^{-1}}}{\left(-\sqrt{1 + x}\right) \cdot \left(\sqrt{1 + x} + \sqrt{x}\right)} \]
        7. rem-square-sqrtN/A

          \[\leadsto \frac{\frac{1}{-\color{blue}{x} \cdot {\left(\sqrt{x}\right)}^{-1}}}{\left(-\sqrt{1 + x}\right) \cdot \left(\sqrt{1 + x} + \sqrt{x}\right)} \]
        8. inv-powN/A

          \[\leadsto \frac{\frac{1}{-x \cdot \color{blue}{\frac{1}{\sqrt{x}}}}}{\left(-\sqrt{1 + x}\right) \cdot \left(\sqrt{1 + x} + \sqrt{x}\right)} \]
        9. div-invN/A

          \[\leadsto \frac{\frac{1}{-\color{blue}{\frac{x}{\sqrt{x}}}}}{\left(-\sqrt{1 + x}\right) \cdot \left(\sqrt{1 + x} + \sqrt{x}\right)} \]
        10. lower-/.f6499.6

          \[\leadsto \frac{\frac{1}{-\color{blue}{\frac{x}{\sqrt{x}}}}}{\left(-\sqrt{1 + x}\right) \cdot \left(\sqrt{1 + x} + \sqrt{x}\right)} \]
      5. Applied rewrites99.6%

        \[\leadsto \frac{\frac{1}{-\color{blue}{\frac{x}{\sqrt{x}}}}}{\left(-\sqrt{1 + x}\right) \cdot \left(\sqrt{1 + x} + \sqrt{x}\right)} \]
      6. Final simplification99.6%

        \[\leadsto \frac{\frac{1}{\frac{x}{\sqrt{x}}}}{\left(\sqrt{1 + x} + \sqrt{x}\right) \cdot \sqrt{1 + x}} \]
      7. Add Preprocessing

      Alternative 3: 99.2% accurate, 0.6× speedup?

      \[\begin{array}{l} \\ \begin{array}{l} t_0 := \sqrt{1 + x}\\ \frac{\frac{\frac{1}{\sqrt{x}}}{t\_0}}{t\_0 + \sqrt{x}} \end{array} \end{array} \]
      (FPCore (x)
       :precision binary64
       (let* ((t_0 (sqrt (+ 1.0 x)))) (/ (/ (/ 1.0 (sqrt x)) t_0) (+ t_0 (sqrt x)))))
      double code(double x) {
      	double t_0 = sqrt((1.0 + x));
      	return ((1.0 / sqrt(x)) / t_0) / (t_0 + sqrt(x));
      }
      
      real(8) function code(x)
          real(8), intent (in) :: x
          real(8) :: t_0
          t_0 = sqrt((1.0d0 + x))
          code = ((1.0d0 / sqrt(x)) / t_0) / (t_0 + sqrt(x))
      end function
      
      public static double code(double x) {
      	double t_0 = Math.sqrt((1.0 + x));
      	return ((1.0 / Math.sqrt(x)) / t_0) / (t_0 + Math.sqrt(x));
      }
      
      def code(x):
      	t_0 = math.sqrt((1.0 + x))
      	return ((1.0 / math.sqrt(x)) / t_0) / (t_0 + math.sqrt(x))
      
      function code(x)
      	t_0 = sqrt(Float64(1.0 + x))
      	return Float64(Float64(Float64(1.0 / sqrt(x)) / t_0) / Float64(t_0 + sqrt(x)))
      end
      
      function tmp = code(x)
      	t_0 = sqrt((1.0 + x));
      	tmp = ((1.0 / sqrt(x)) / t_0) / (t_0 + sqrt(x));
      end
      
      code[x_] := Block[{t$95$0 = N[Sqrt[N[(1.0 + x), $MachinePrecision]], $MachinePrecision]}, N[(N[(N[(1.0 / N[Sqrt[x], $MachinePrecision]), $MachinePrecision] / t$95$0), $MachinePrecision] / N[(t$95$0 + N[Sqrt[x], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]]
      
      \begin{array}{l}
      
      \\
      \begin{array}{l}
      t_0 := \sqrt{1 + x}\\
      \frac{\frac{\frac{1}{\sqrt{x}}}{t\_0}}{t\_0 + \sqrt{x}}
      \end{array}
      \end{array}
      
      Derivation
      1. Initial program 39.1%

        \[\frac{1}{\sqrt{x}} - \frac{1}{\sqrt{x + 1}} \]
      2. Add Preprocessing
      3. Step-by-step derivation
        1. lift--.f64N/A

          \[\leadsto \color{blue}{\frac{1}{\sqrt{x}} - \frac{1}{\sqrt{x + 1}}} \]
        2. lift-/.f64N/A

          \[\leadsto \color{blue}{\frac{1}{\sqrt{x}}} - \frac{1}{\sqrt{x + 1}} \]
        3. lift-/.f64N/A

          \[\leadsto \frac{1}{\sqrt{x}} - \color{blue}{\frac{1}{\sqrt{x + 1}}} \]
        4. frac-subN/A

          \[\leadsto \color{blue}{\frac{1 \cdot \sqrt{x + 1} - \sqrt{x} \cdot 1}{\sqrt{x} \cdot \sqrt{x + 1}}} \]
        5. div-invN/A

          \[\leadsto \color{blue}{\left(1 \cdot \sqrt{x + 1} - \sqrt{x} \cdot 1\right) \cdot \frac{1}{\sqrt{x} \cdot \sqrt{x + 1}}} \]
        6. metadata-evalN/A

          \[\leadsto \left(1 \cdot \sqrt{x + 1} - \sqrt{x} \cdot \color{blue}{\frac{1}{1}}\right) \cdot \frac{1}{\sqrt{x} \cdot \sqrt{x + 1}} \]
        7. div-invN/A

          \[\leadsto \left(1 \cdot \sqrt{x + 1} - \color{blue}{\frac{\sqrt{x}}{1}}\right) \cdot \frac{1}{\sqrt{x} \cdot \sqrt{x + 1}} \]
        8. *-lft-identityN/A

          \[\leadsto \left(\color{blue}{\sqrt{x + 1}} - \frac{\sqrt{x}}{1}\right) \cdot \frac{1}{\sqrt{x} \cdot \sqrt{x + 1}} \]
        9. flip--N/A

          \[\leadsto \color{blue}{\frac{\sqrt{x + 1} \cdot \sqrt{x + 1} - \frac{\sqrt{x}}{1} \cdot \frac{\sqrt{x}}{1}}{\sqrt{x + 1} + \frac{\sqrt{x}}{1}}} \cdot \frac{1}{\sqrt{x} \cdot \sqrt{x + 1}} \]
        10. metadata-evalN/A

          \[\leadsto \frac{\sqrt{x + 1} \cdot \sqrt{x + 1} - \frac{\sqrt{x}}{1} \cdot \frac{\sqrt{x}}{1}}{\sqrt{x + 1} + \frac{\sqrt{x}}{1}} \cdot \frac{\color{blue}{1 \cdot 1}}{\sqrt{x} \cdot \sqrt{x + 1}} \]
        11. frac-timesN/A

          \[\leadsto \frac{\sqrt{x + 1} \cdot \sqrt{x + 1} - \frac{\sqrt{x}}{1} \cdot \frac{\sqrt{x}}{1}}{\sqrt{x + 1} + \frac{\sqrt{x}}{1}} \cdot \color{blue}{\left(\frac{1}{\sqrt{x}} \cdot \frac{1}{\sqrt{x + 1}}\right)} \]
        12. lift-/.f64N/A

          \[\leadsto \frac{\sqrt{x + 1} \cdot \sqrt{x + 1} - \frac{\sqrt{x}}{1} \cdot \frac{\sqrt{x}}{1}}{\sqrt{x + 1} + \frac{\sqrt{x}}{1}} \cdot \left(\color{blue}{\frac{1}{\sqrt{x}}} \cdot \frac{1}{\sqrt{x + 1}}\right) \]
        13. frac-2negN/A

          \[\leadsto \frac{\sqrt{x + 1} \cdot \sqrt{x + 1} - \frac{\sqrt{x}}{1} \cdot \frac{\sqrt{x}}{1}}{\sqrt{x + 1} + \frac{\sqrt{x}}{1}} \cdot \left(\frac{1}{\sqrt{x}} \cdot \color{blue}{\frac{\mathsf{neg}\left(1\right)}{\mathsf{neg}\left(\sqrt{x + 1}\right)}}\right) \]
        14. metadata-evalN/A

          \[\leadsto \frac{\sqrt{x + 1} \cdot \sqrt{x + 1} - \frac{\sqrt{x}}{1} \cdot \frac{\sqrt{x}}{1}}{\sqrt{x + 1} + \frac{\sqrt{x}}{1}} \cdot \left(\frac{1}{\sqrt{x}} \cdot \frac{\color{blue}{-1}}{\mathsf{neg}\left(\sqrt{x + 1}\right)}\right) \]
        15. associate-*r/N/A

          \[\leadsto \frac{\sqrt{x + 1} \cdot \sqrt{x + 1} - \frac{\sqrt{x}}{1} \cdot \frac{\sqrt{x}}{1}}{\sqrt{x + 1} + \frac{\sqrt{x}}{1}} \cdot \color{blue}{\frac{\frac{1}{\sqrt{x}} \cdot -1}{\mathsf{neg}\left(\sqrt{x + 1}\right)}} \]
      4. Applied rewrites41.1%

        \[\leadsto \color{blue}{\frac{\left(\left(x + 1\right) - x\right) \cdot \frac{-1}{\sqrt{x}}}{\left(\sqrt{x} + \sqrt{x + 1}\right) \cdot \left(-\sqrt{x + 1}\right)}} \]
      5. Taylor expanded in x around 0

        \[\leadsto \frac{\color{blue}{1} \cdot \frac{-1}{\sqrt{x}}}{\left(\sqrt{x} + \sqrt{x + 1}\right) \cdot \left(-\sqrt{x + 1}\right)} \]
      6. Step-by-step derivation
        1. Applied rewrites99.3%

          \[\leadsto \frac{\color{blue}{1} \cdot \frac{-1}{\sqrt{x}}}{\left(\sqrt{x} + \sqrt{x + 1}\right) \cdot \left(-\sqrt{x + 1}\right)} \]
        2. Step-by-step derivation
          1. lift-/.f64N/A

            \[\leadsto \color{blue}{\frac{1 \cdot \frac{-1}{\sqrt{x}}}{\left(\sqrt{x} + \sqrt{x + 1}\right) \cdot \left(-\sqrt{x + 1}\right)}} \]
          2. lift-*.f64N/A

            \[\leadsto \frac{1 \cdot \frac{-1}{\sqrt{x}}}{\color{blue}{\left(\sqrt{x} + \sqrt{x + 1}\right) \cdot \left(-\sqrt{x + 1}\right)}} \]
          3. *-commutativeN/A

            \[\leadsto \frac{1 \cdot \frac{-1}{\sqrt{x}}}{\color{blue}{\left(-\sqrt{x + 1}\right) \cdot \left(\sqrt{x} + \sqrt{x + 1}\right)}} \]
          4. associate-/r*N/A

            \[\leadsto \color{blue}{\frac{\frac{1 \cdot \frac{-1}{\sqrt{x}}}{-\sqrt{x + 1}}}{\sqrt{x} + \sqrt{x + 1}}} \]
          5. lower-/.f64N/A

            \[\leadsto \color{blue}{\frac{\frac{1 \cdot \frac{-1}{\sqrt{x}}}{-\sqrt{x + 1}}}{\sqrt{x} + \sqrt{x + 1}}} \]
        3. Applied rewrites99.3%

          \[\leadsto \color{blue}{\frac{\frac{\frac{1}{-\sqrt{x}}}{-\sqrt{1 + x}}}{\sqrt{1 + x} + \sqrt{x}}} \]
        4. Final simplification99.3%

          \[\leadsto \frac{\frac{\frac{1}{\sqrt{x}}}{\sqrt{1 + x}}}{\sqrt{1 + x} + \sqrt{x}} \]
        5. Add Preprocessing

        Alternative 4: 99.2% accurate, 0.6× speedup?

        \[\begin{array}{l} \\ \begin{array}{l} t_0 := \sqrt{1 + x}\\ \frac{\frac{1}{\sqrt{x}}}{\left(t\_0 + \sqrt{x}\right) \cdot t\_0} \end{array} \end{array} \]
        (FPCore (x)
         :precision binary64
         (let* ((t_0 (sqrt (+ 1.0 x)))) (/ (/ 1.0 (sqrt x)) (* (+ t_0 (sqrt x)) t_0))))
        double code(double x) {
        	double t_0 = sqrt((1.0 + x));
        	return (1.0 / sqrt(x)) / ((t_0 + sqrt(x)) * t_0);
        }
        
        real(8) function code(x)
            real(8), intent (in) :: x
            real(8) :: t_0
            t_0 = sqrt((1.0d0 + x))
            code = (1.0d0 / sqrt(x)) / ((t_0 + sqrt(x)) * t_0)
        end function
        
        public static double code(double x) {
        	double t_0 = Math.sqrt((1.0 + x));
        	return (1.0 / Math.sqrt(x)) / ((t_0 + Math.sqrt(x)) * t_0);
        }
        
        def code(x):
        	t_0 = math.sqrt((1.0 + x))
        	return (1.0 / math.sqrt(x)) / ((t_0 + math.sqrt(x)) * t_0)
        
        function code(x)
        	t_0 = sqrt(Float64(1.0 + x))
        	return Float64(Float64(1.0 / sqrt(x)) / Float64(Float64(t_0 + sqrt(x)) * t_0))
        end
        
        function tmp = code(x)
        	t_0 = sqrt((1.0 + x));
        	tmp = (1.0 / sqrt(x)) / ((t_0 + sqrt(x)) * t_0);
        end
        
        code[x_] := Block[{t$95$0 = N[Sqrt[N[(1.0 + x), $MachinePrecision]], $MachinePrecision]}, N[(N[(1.0 / N[Sqrt[x], $MachinePrecision]), $MachinePrecision] / N[(N[(t$95$0 + N[Sqrt[x], $MachinePrecision]), $MachinePrecision] * t$95$0), $MachinePrecision]), $MachinePrecision]]
        
        \begin{array}{l}
        
        \\
        \begin{array}{l}
        t_0 := \sqrt{1 + x}\\
        \frac{\frac{1}{\sqrt{x}}}{\left(t\_0 + \sqrt{x}\right) \cdot t\_0}
        \end{array}
        \end{array}
        
        Derivation
        1. Initial program 39.1%

          \[\frac{1}{\sqrt{x}} - \frac{1}{\sqrt{x + 1}} \]
        2. Add Preprocessing
        3. Step-by-step derivation
          1. lift--.f64N/A

            \[\leadsto \color{blue}{\frac{1}{\sqrt{x}} - \frac{1}{\sqrt{x + 1}}} \]
          2. lift-/.f64N/A

            \[\leadsto \color{blue}{\frac{1}{\sqrt{x}}} - \frac{1}{\sqrt{x + 1}} \]
          3. lift-/.f64N/A

            \[\leadsto \frac{1}{\sqrt{x}} - \color{blue}{\frac{1}{\sqrt{x + 1}}} \]
          4. frac-subN/A

            \[\leadsto \color{blue}{\frac{1 \cdot \sqrt{x + 1} - \sqrt{x} \cdot 1}{\sqrt{x} \cdot \sqrt{x + 1}}} \]
          5. div-invN/A

            \[\leadsto \color{blue}{\left(1 \cdot \sqrt{x + 1} - \sqrt{x} \cdot 1\right) \cdot \frac{1}{\sqrt{x} \cdot \sqrt{x + 1}}} \]
          6. metadata-evalN/A

            \[\leadsto \left(1 \cdot \sqrt{x + 1} - \sqrt{x} \cdot \color{blue}{\frac{1}{1}}\right) \cdot \frac{1}{\sqrt{x} \cdot \sqrt{x + 1}} \]
          7. div-invN/A

            \[\leadsto \left(1 \cdot \sqrt{x + 1} - \color{blue}{\frac{\sqrt{x}}{1}}\right) \cdot \frac{1}{\sqrt{x} \cdot \sqrt{x + 1}} \]
          8. *-lft-identityN/A

            \[\leadsto \left(\color{blue}{\sqrt{x + 1}} - \frac{\sqrt{x}}{1}\right) \cdot \frac{1}{\sqrt{x} \cdot \sqrt{x + 1}} \]
          9. flip--N/A

            \[\leadsto \color{blue}{\frac{\sqrt{x + 1} \cdot \sqrt{x + 1} - \frac{\sqrt{x}}{1} \cdot \frac{\sqrt{x}}{1}}{\sqrt{x + 1} + \frac{\sqrt{x}}{1}}} \cdot \frac{1}{\sqrt{x} \cdot \sqrt{x + 1}} \]
          10. metadata-evalN/A

            \[\leadsto \frac{\sqrt{x + 1} \cdot \sqrt{x + 1} - \frac{\sqrt{x}}{1} \cdot \frac{\sqrt{x}}{1}}{\sqrt{x + 1} + \frac{\sqrt{x}}{1}} \cdot \frac{\color{blue}{1 \cdot 1}}{\sqrt{x} \cdot \sqrt{x + 1}} \]
          11. frac-timesN/A

            \[\leadsto \frac{\sqrt{x + 1} \cdot \sqrt{x + 1} - \frac{\sqrt{x}}{1} \cdot \frac{\sqrt{x}}{1}}{\sqrt{x + 1} + \frac{\sqrt{x}}{1}} \cdot \color{blue}{\left(\frac{1}{\sqrt{x}} \cdot \frac{1}{\sqrt{x + 1}}\right)} \]
          12. lift-/.f64N/A

            \[\leadsto \frac{\sqrt{x + 1} \cdot \sqrt{x + 1} - \frac{\sqrt{x}}{1} \cdot \frac{\sqrt{x}}{1}}{\sqrt{x + 1} + \frac{\sqrt{x}}{1}} \cdot \left(\color{blue}{\frac{1}{\sqrt{x}}} \cdot \frac{1}{\sqrt{x + 1}}\right) \]
          13. frac-2negN/A

            \[\leadsto \frac{\sqrt{x + 1} \cdot \sqrt{x + 1} - \frac{\sqrt{x}}{1} \cdot \frac{\sqrt{x}}{1}}{\sqrt{x + 1} + \frac{\sqrt{x}}{1}} \cdot \left(\frac{1}{\sqrt{x}} \cdot \color{blue}{\frac{\mathsf{neg}\left(1\right)}{\mathsf{neg}\left(\sqrt{x + 1}\right)}}\right) \]
          14. metadata-evalN/A

            \[\leadsto \frac{\sqrt{x + 1} \cdot \sqrt{x + 1} - \frac{\sqrt{x}}{1} \cdot \frac{\sqrt{x}}{1}}{\sqrt{x + 1} + \frac{\sqrt{x}}{1}} \cdot \left(\frac{1}{\sqrt{x}} \cdot \frac{\color{blue}{-1}}{\mathsf{neg}\left(\sqrt{x + 1}\right)}\right) \]
          15. associate-*r/N/A

            \[\leadsto \frac{\sqrt{x + 1} \cdot \sqrt{x + 1} - \frac{\sqrt{x}}{1} \cdot \frac{\sqrt{x}}{1}}{\sqrt{x + 1} + \frac{\sqrt{x}}{1}} \cdot \color{blue}{\frac{\frac{1}{\sqrt{x}} \cdot -1}{\mathsf{neg}\left(\sqrt{x + 1}\right)}} \]
        4. Applied rewrites41.1%

          \[\leadsto \color{blue}{\frac{\left(\left(x + 1\right) - x\right) \cdot \frac{-1}{\sqrt{x}}}{\left(\sqrt{x} + \sqrt{x + 1}\right) \cdot \left(-\sqrt{x + 1}\right)}} \]
        5. Taylor expanded in x around 0

          \[\leadsto \frac{\color{blue}{1} \cdot \frac{-1}{\sqrt{x}}}{\left(\sqrt{x} + \sqrt{x + 1}\right) \cdot \left(-\sqrt{x + 1}\right)} \]
        6. Step-by-step derivation
          1. Applied rewrites99.3%

            \[\leadsto \frac{\color{blue}{1} \cdot \frac{-1}{\sqrt{x}}}{\left(\sqrt{x} + \sqrt{x + 1}\right) \cdot \left(-\sqrt{x + 1}\right)} \]
          2. Step-by-step derivation
            1. lift-*.f64N/A

              \[\leadsto \frac{\color{blue}{1 \cdot \frac{-1}{\sqrt{x}}}}{\left(\sqrt{x} + \sqrt{x + 1}\right) \cdot \left(-\sqrt{x + 1}\right)} \]
            2. lift-/.f64N/A

              \[\leadsto \frac{1 \cdot \color{blue}{\frac{-1}{\sqrt{x}}}}{\left(\sqrt{x} + \sqrt{x + 1}\right) \cdot \left(-\sqrt{x + 1}\right)} \]
            3. frac-2negN/A

              \[\leadsto \frac{1 \cdot \color{blue}{\frac{\mathsf{neg}\left(-1\right)}{\mathsf{neg}\left(\sqrt{x}\right)}}}{\left(\sqrt{x} + \sqrt{x + 1}\right) \cdot \left(-\sqrt{x + 1}\right)} \]
            4. metadata-evalN/A

              \[\leadsto \frac{1 \cdot \frac{\color{blue}{1}}{\mathsf{neg}\left(\sqrt{x}\right)}}{\left(\sqrt{x} + \sqrt{x + 1}\right) \cdot \left(-\sqrt{x + 1}\right)} \]
            5. un-div-invN/A

              \[\leadsto \frac{\color{blue}{\frac{1}{\mathsf{neg}\left(\sqrt{x}\right)}}}{\left(\sqrt{x} + \sqrt{x + 1}\right) \cdot \left(-\sqrt{x + 1}\right)} \]
            6. lower-/.f64N/A

              \[\leadsto \frac{\color{blue}{\frac{1}{\mathsf{neg}\left(\sqrt{x}\right)}}}{\left(\sqrt{x} + \sqrt{x + 1}\right) \cdot \left(-\sqrt{x + 1}\right)} \]
            7. lower-neg.f6499.3

              \[\leadsto \frac{\frac{1}{\color{blue}{-\sqrt{x}}}}{\left(\sqrt{x} + \sqrt{x + 1}\right) \cdot \left(-\sqrt{x + 1}\right)} \]
            8. lift-*.f64N/A

              \[\leadsto \frac{\frac{1}{-\sqrt{x}}}{\color{blue}{\left(\sqrt{x} + \sqrt{x + 1}\right) \cdot \left(-\sqrt{x + 1}\right)}} \]
            9. *-commutativeN/A

              \[\leadsto \frac{\frac{1}{-\sqrt{x}}}{\color{blue}{\left(-\sqrt{x + 1}\right) \cdot \left(\sqrt{x} + \sqrt{x + 1}\right)}} \]
            10. lower-*.f6499.3

              \[\leadsto \frac{\frac{1}{-\sqrt{x}}}{\color{blue}{\left(-\sqrt{x + 1}\right) \cdot \left(\sqrt{x} + \sqrt{x + 1}\right)}} \]
            11. lift-+.f64N/A

              \[\leadsto \frac{\frac{1}{-\sqrt{x}}}{\left(-\sqrt{\color{blue}{x + 1}}\right) \cdot \left(\sqrt{x} + \sqrt{x + 1}\right)} \]
            12. +-commutativeN/A

              \[\leadsto \frac{\frac{1}{-\sqrt{x}}}{\left(-\sqrt{\color{blue}{1 + x}}\right) \cdot \left(\sqrt{x} + \sqrt{x + 1}\right)} \]
            13. lower-+.f6499.3

              \[\leadsto \frac{\frac{1}{-\sqrt{x}}}{\left(-\sqrt{\color{blue}{1 + x}}\right) \cdot \left(\sqrt{x} + \sqrt{x + 1}\right)} \]
            14. lift-+.f64N/A

              \[\leadsto \frac{\frac{1}{-\sqrt{x}}}{\left(-\sqrt{1 + x}\right) \cdot \color{blue}{\left(\sqrt{x} + \sqrt{x + 1}\right)}} \]
            15. +-commutativeN/A

              \[\leadsto \frac{\frac{1}{-\sqrt{x}}}{\left(-\sqrt{1 + x}\right) \cdot \color{blue}{\left(\sqrt{x + 1} + \sqrt{x}\right)}} \]
            16. lower-+.f6499.3

              \[\leadsto \frac{\frac{1}{-\sqrt{x}}}{\left(-\sqrt{1 + x}\right) \cdot \color{blue}{\left(\sqrt{x + 1} + \sqrt{x}\right)}} \]
            17. lift-+.f64N/A

              \[\leadsto \frac{\frac{1}{-\sqrt{x}}}{\left(-\sqrt{1 + x}\right) \cdot \left(\sqrt{\color{blue}{x + 1}} + \sqrt{x}\right)} \]
            18. +-commutativeN/A

              \[\leadsto \frac{\frac{1}{-\sqrt{x}}}{\left(-\sqrt{1 + x}\right) \cdot \left(\sqrt{\color{blue}{1 + x}} + \sqrt{x}\right)} \]
            19. lower-+.f6499.3

              \[\leadsto \frac{\frac{1}{-\sqrt{x}}}{\left(-\sqrt{1 + x}\right) \cdot \left(\sqrt{\color{blue}{1 + x}} + \sqrt{x}\right)} \]
          3. Applied rewrites99.3%

            \[\leadsto \color{blue}{\frac{\frac{1}{-\sqrt{x}}}{\left(-\sqrt{1 + x}\right) \cdot \left(\sqrt{1 + x} + \sqrt{x}\right)}} \]
          4. Final simplification99.3%

            \[\leadsto \frac{\frac{1}{\sqrt{x}}}{\left(\sqrt{1 + x} + \sqrt{x}\right) \cdot \sqrt{1 + x}} \]
          5. Add Preprocessing

          Alternative 5: 99.1% accurate, 0.7× speedup?

          \[\begin{array}{l} \\ \frac{\frac{\left(\frac{0.125}{x} - 0.5\right) - \frac{0.0625}{x \cdot x}}{x}}{-\sqrt{1 + x}} \end{array} \]
          (FPCore (x)
           :precision binary64
           (/ (/ (- (- (/ 0.125 x) 0.5) (/ 0.0625 (* x x))) x) (- (sqrt (+ 1.0 x)))))
          double code(double x) {
          	return ((((0.125 / x) - 0.5) - (0.0625 / (x * x))) / x) / -sqrt((1.0 + x));
          }
          
          real(8) function code(x)
              real(8), intent (in) :: x
              code = ((((0.125d0 / x) - 0.5d0) - (0.0625d0 / (x * x))) / x) / -sqrt((1.0d0 + x))
          end function
          
          public static double code(double x) {
          	return ((((0.125 / x) - 0.5) - (0.0625 / (x * x))) / x) / -Math.sqrt((1.0 + x));
          }
          
          def code(x):
          	return ((((0.125 / x) - 0.5) - (0.0625 / (x * x))) / x) / -math.sqrt((1.0 + x))
          
          function code(x)
          	return Float64(Float64(Float64(Float64(Float64(0.125 / x) - 0.5) - Float64(0.0625 / Float64(x * x))) / x) / Float64(-sqrt(Float64(1.0 + x))))
          end
          
          function tmp = code(x)
          	tmp = ((((0.125 / x) - 0.5) - (0.0625 / (x * x))) / x) / -sqrt((1.0 + x));
          end
          
          code[x_] := N[(N[(N[(N[(N[(0.125 / x), $MachinePrecision] - 0.5), $MachinePrecision] - N[(0.0625 / N[(x * x), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / x), $MachinePrecision] / (-N[Sqrt[N[(1.0 + x), $MachinePrecision]], $MachinePrecision])), $MachinePrecision]
          
          \begin{array}{l}
          
          \\
          \frac{\frac{\left(\frac{0.125}{x} - 0.5\right) - \frac{0.0625}{x \cdot x}}{x}}{-\sqrt{1 + x}}
          \end{array}
          
          Derivation
          1. Initial program 39.1%

            \[\frac{1}{\sqrt{x}} - \frac{1}{\sqrt{x + 1}} \]
          2. Add Preprocessing
          3. Step-by-step derivation
            1. lift--.f64N/A

              \[\leadsto \color{blue}{\frac{1}{\sqrt{x}} - \frac{1}{\sqrt{x + 1}}} \]
            2. lift-/.f64N/A

              \[\leadsto \color{blue}{\frac{1}{\sqrt{x}}} - \frac{1}{\sqrt{x + 1}} \]
            3. lift-/.f64N/A

              \[\leadsto \frac{1}{\sqrt{x}} - \color{blue}{\frac{1}{\sqrt{x + 1}}} \]
            4. frac-subN/A

              \[\leadsto \color{blue}{\frac{1 \cdot \sqrt{x + 1} - \sqrt{x} \cdot 1}{\sqrt{x} \cdot \sqrt{x + 1}}} \]
            5. div-invN/A

              \[\leadsto \color{blue}{\left(1 \cdot \sqrt{x + 1} - \sqrt{x} \cdot 1\right) \cdot \frac{1}{\sqrt{x} \cdot \sqrt{x + 1}}} \]
            6. metadata-evalN/A

              \[\leadsto \left(1 \cdot \sqrt{x + 1} - \sqrt{x} \cdot \color{blue}{\frac{1}{1}}\right) \cdot \frac{1}{\sqrt{x} \cdot \sqrt{x + 1}} \]
            7. div-invN/A

              \[\leadsto \left(1 \cdot \sqrt{x + 1} - \color{blue}{\frac{\sqrt{x}}{1}}\right) \cdot \frac{1}{\sqrt{x} \cdot \sqrt{x + 1}} \]
            8. *-lft-identityN/A

              \[\leadsto \left(\color{blue}{\sqrt{x + 1}} - \frac{\sqrt{x}}{1}\right) \cdot \frac{1}{\sqrt{x} \cdot \sqrt{x + 1}} \]
            9. flip--N/A

              \[\leadsto \color{blue}{\frac{\sqrt{x + 1} \cdot \sqrt{x + 1} - \frac{\sqrt{x}}{1} \cdot \frac{\sqrt{x}}{1}}{\sqrt{x + 1} + \frac{\sqrt{x}}{1}}} \cdot \frac{1}{\sqrt{x} \cdot \sqrt{x + 1}} \]
            10. metadata-evalN/A

              \[\leadsto \frac{\sqrt{x + 1} \cdot \sqrt{x + 1} - \frac{\sqrt{x}}{1} \cdot \frac{\sqrt{x}}{1}}{\sqrt{x + 1} + \frac{\sqrt{x}}{1}} \cdot \frac{\color{blue}{1 \cdot 1}}{\sqrt{x} \cdot \sqrt{x + 1}} \]
            11. frac-timesN/A

              \[\leadsto \frac{\sqrt{x + 1} \cdot \sqrt{x + 1} - \frac{\sqrt{x}}{1} \cdot \frac{\sqrt{x}}{1}}{\sqrt{x + 1} + \frac{\sqrt{x}}{1}} \cdot \color{blue}{\left(\frac{1}{\sqrt{x}} \cdot \frac{1}{\sqrt{x + 1}}\right)} \]
            12. lift-/.f64N/A

              \[\leadsto \frac{\sqrt{x + 1} \cdot \sqrt{x + 1} - \frac{\sqrt{x}}{1} \cdot \frac{\sqrt{x}}{1}}{\sqrt{x + 1} + \frac{\sqrt{x}}{1}} \cdot \left(\color{blue}{\frac{1}{\sqrt{x}}} \cdot \frac{1}{\sqrt{x + 1}}\right) \]
            13. frac-2negN/A

              \[\leadsto \frac{\sqrt{x + 1} \cdot \sqrt{x + 1} - \frac{\sqrt{x}}{1} \cdot \frac{\sqrt{x}}{1}}{\sqrt{x + 1} + \frac{\sqrt{x}}{1}} \cdot \left(\frac{1}{\sqrt{x}} \cdot \color{blue}{\frac{\mathsf{neg}\left(1\right)}{\mathsf{neg}\left(\sqrt{x + 1}\right)}}\right) \]
            14. metadata-evalN/A

              \[\leadsto \frac{\sqrt{x + 1} \cdot \sqrt{x + 1} - \frac{\sqrt{x}}{1} \cdot \frac{\sqrt{x}}{1}}{\sqrt{x + 1} + \frac{\sqrt{x}}{1}} \cdot \left(\frac{1}{\sqrt{x}} \cdot \frac{\color{blue}{-1}}{\mathsf{neg}\left(\sqrt{x + 1}\right)}\right) \]
            15. associate-*r/N/A

              \[\leadsto \frac{\sqrt{x + 1} \cdot \sqrt{x + 1} - \frac{\sqrt{x}}{1} \cdot \frac{\sqrt{x}}{1}}{\sqrt{x + 1} + \frac{\sqrt{x}}{1}} \cdot \color{blue}{\frac{\frac{1}{\sqrt{x}} \cdot -1}{\mathsf{neg}\left(\sqrt{x + 1}\right)}} \]
          4. Applied rewrites41.1%

            \[\leadsto \color{blue}{\frac{\left(\left(x + 1\right) - x\right) \cdot \frac{-1}{\sqrt{x}}}{\left(\sqrt{x} + \sqrt{x + 1}\right) \cdot \left(-\sqrt{x + 1}\right)}} \]
          5. Taylor expanded in x around 0

            \[\leadsto \frac{\color{blue}{1} \cdot \frac{-1}{\sqrt{x}}}{\left(\sqrt{x} + \sqrt{x + 1}\right) \cdot \left(-\sqrt{x + 1}\right)} \]
          6. Step-by-step derivation
            1. Applied rewrites99.3%

              \[\leadsto \frac{\color{blue}{1} \cdot \frac{-1}{\sqrt{x}}}{\left(\sqrt{x} + \sqrt{x + 1}\right) \cdot \left(-\sqrt{x + 1}\right)} \]
            2. Step-by-step derivation
              1. lift-/.f64N/A

                \[\leadsto \color{blue}{\frac{1 \cdot \frac{-1}{\sqrt{x}}}{\left(\sqrt{x} + \sqrt{x + 1}\right) \cdot \left(-\sqrt{x + 1}\right)}} \]
              2. lift-*.f64N/A

                \[\leadsto \frac{1 \cdot \frac{-1}{\sqrt{x}}}{\color{blue}{\left(\sqrt{x} + \sqrt{x + 1}\right) \cdot \left(-\sqrt{x + 1}\right)}} \]
              3. associate-/r*N/A

                \[\leadsto \color{blue}{\frac{\frac{1 \cdot \frac{-1}{\sqrt{x}}}{\sqrt{x} + \sqrt{x + 1}}}{-\sqrt{x + 1}}} \]
              4. lower-/.f64N/A

                \[\leadsto \color{blue}{\frac{\frac{1 \cdot \frac{-1}{\sqrt{x}}}{\sqrt{x} + \sqrt{x + 1}}}{-\sqrt{x + 1}}} \]
            3. Applied rewrites99.7%

              \[\leadsto \color{blue}{\frac{\frac{1 \cdot -1}{\mathsf{hypot}\left(\sqrt{x}, x\right) + x}}{-\sqrt{1 + x}}} \]
            4. Taylor expanded in x around inf

              \[\leadsto \frac{\color{blue}{\frac{\frac{1}{8} \cdot \frac{1}{x} - \left(\frac{1}{2} + \frac{\frac{1}{16}}{{x}^{2}}\right)}{x}}}{-\sqrt{1 + x}} \]
            5. Step-by-step derivation
              1. lower-/.f64N/A

                \[\leadsto \frac{\color{blue}{\frac{\frac{1}{8} \cdot \frac{1}{x} - \left(\frac{1}{2} + \frac{\frac{1}{16}}{{x}^{2}}\right)}{x}}}{-\sqrt{1 + x}} \]
              2. associate--r+N/A

                \[\leadsto \frac{\frac{\color{blue}{\left(\frac{1}{8} \cdot \frac{1}{x} - \frac{1}{2}\right) - \frac{\frac{1}{16}}{{x}^{2}}}}{x}}{-\sqrt{1 + x}} \]
              3. lower--.f64N/A

                \[\leadsto \frac{\frac{\color{blue}{\left(\frac{1}{8} \cdot \frac{1}{x} - \frac{1}{2}\right) - \frac{\frac{1}{16}}{{x}^{2}}}}{x}}{-\sqrt{1 + x}} \]
              4. lower--.f64N/A

                \[\leadsto \frac{\frac{\color{blue}{\left(\frac{1}{8} \cdot \frac{1}{x} - \frac{1}{2}\right)} - \frac{\frac{1}{16}}{{x}^{2}}}{x}}{-\sqrt{1 + x}} \]
              5. associate-*r/N/A

                \[\leadsto \frac{\frac{\left(\color{blue}{\frac{\frac{1}{8} \cdot 1}{x}} - \frac{1}{2}\right) - \frac{\frac{1}{16}}{{x}^{2}}}{x}}{-\sqrt{1 + x}} \]
              6. metadata-evalN/A

                \[\leadsto \frac{\frac{\left(\frac{\color{blue}{\frac{1}{8}}}{x} - \frac{1}{2}\right) - \frac{\frac{1}{16}}{{x}^{2}}}{x}}{-\sqrt{1 + x}} \]
              7. lower-/.f64N/A

                \[\leadsto \frac{\frac{\left(\color{blue}{\frac{\frac{1}{8}}{x}} - \frac{1}{2}\right) - \frac{\frac{1}{16}}{{x}^{2}}}{x}}{-\sqrt{1 + x}} \]
              8. lower-/.f64N/A

                \[\leadsto \frac{\frac{\left(\frac{\frac{1}{8}}{x} - \frac{1}{2}\right) - \color{blue}{\frac{\frac{1}{16}}{{x}^{2}}}}{x}}{-\sqrt{1 + x}} \]
              9. unpow2N/A

                \[\leadsto \frac{\frac{\left(\frac{\frac{1}{8}}{x} - \frac{1}{2}\right) - \frac{\frac{1}{16}}{\color{blue}{x \cdot x}}}{x}}{-\sqrt{1 + x}} \]
              10. lower-*.f6499.3

                \[\leadsto \frac{\frac{\left(\frac{0.125}{x} - 0.5\right) - \frac{0.0625}{\color{blue}{x \cdot x}}}{x}}{-\sqrt{1 + x}} \]
            6. Applied rewrites99.3%

              \[\leadsto \frac{\color{blue}{\frac{\left(\frac{0.125}{x} - 0.5\right) - \frac{0.0625}{x \cdot x}}{x}}}{-\sqrt{1 + x}} \]
            7. Add Preprocessing

            Alternative 6: 98.8% accurate, 0.9× speedup?

            \[\begin{array}{l} \\ \frac{\frac{1}{\left(\frac{0.5}{x} + 2\right) \cdot x}}{\sqrt{1 + x}} \end{array} \]
            (FPCore (x)
             :precision binary64
             (/ (/ 1.0 (* (+ (/ 0.5 x) 2.0) x)) (sqrt (+ 1.0 x))))
            double code(double x) {
            	return (1.0 / (((0.5 / x) + 2.0) * x)) / sqrt((1.0 + x));
            }
            
            real(8) function code(x)
                real(8), intent (in) :: x
                code = (1.0d0 / (((0.5d0 / x) + 2.0d0) * x)) / sqrt((1.0d0 + x))
            end function
            
            public static double code(double x) {
            	return (1.0 / (((0.5 / x) + 2.0) * x)) / Math.sqrt((1.0 + x));
            }
            
            def code(x):
            	return (1.0 / (((0.5 / x) + 2.0) * x)) / math.sqrt((1.0 + x))
            
            function code(x)
            	return Float64(Float64(1.0 / Float64(Float64(Float64(0.5 / x) + 2.0) * x)) / sqrt(Float64(1.0 + x)))
            end
            
            function tmp = code(x)
            	tmp = (1.0 / (((0.5 / x) + 2.0) * x)) / sqrt((1.0 + x));
            end
            
            code[x_] := N[(N[(1.0 / N[(N[(N[(0.5 / x), $MachinePrecision] + 2.0), $MachinePrecision] * x), $MachinePrecision]), $MachinePrecision] / N[Sqrt[N[(1.0 + x), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]
            
            \begin{array}{l}
            
            \\
            \frac{\frac{1}{\left(\frac{0.5}{x} + 2\right) \cdot x}}{\sqrt{1 + x}}
            \end{array}
            
            Derivation
            1. Initial program 39.1%

              \[\frac{1}{\sqrt{x}} - \frac{1}{\sqrt{x + 1}} \]
            2. Add Preprocessing
            3. Step-by-step derivation
              1. lift--.f64N/A

                \[\leadsto \color{blue}{\frac{1}{\sqrt{x}} - \frac{1}{\sqrt{x + 1}}} \]
              2. lift-/.f64N/A

                \[\leadsto \color{blue}{\frac{1}{\sqrt{x}}} - \frac{1}{\sqrt{x + 1}} \]
              3. lift-/.f64N/A

                \[\leadsto \frac{1}{\sqrt{x}} - \color{blue}{\frac{1}{\sqrt{x + 1}}} \]
              4. frac-subN/A

                \[\leadsto \color{blue}{\frac{1 \cdot \sqrt{x + 1} - \sqrt{x} \cdot 1}{\sqrt{x} \cdot \sqrt{x + 1}}} \]
              5. div-invN/A

                \[\leadsto \color{blue}{\left(1 \cdot \sqrt{x + 1} - \sqrt{x} \cdot 1\right) \cdot \frac{1}{\sqrt{x} \cdot \sqrt{x + 1}}} \]
              6. metadata-evalN/A

                \[\leadsto \left(1 \cdot \sqrt{x + 1} - \sqrt{x} \cdot \color{blue}{\frac{1}{1}}\right) \cdot \frac{1}{\sqrt{x} \cdot \sqrt{x + 1}} \]
              7. div-invN/A

                \[\leadsto \left(1 \cdot \sqrt{x + 1} - \color{blue}{\frac{\sqrt{x}}{1}}\right) \cdot \frac{1}{\sqrt{x} \cdot \sqrt{x + 1}} \]
              8. *-lft-identityN/A

                \[\leadsto \left(\color{blue}{\sqrt{x + 1}} - \frac{\sqrt{x}}{1}\right) \cdot \frac{1}{\sqrt{x} \cdot \sqrt{x + 1}} \]
              9. flip--N/A

                \[\leadsto \color{blue}{\frac{\sqrt{x + 1} \cdot \sqrt{x + 1} - \frac{\sqrt{x}}{1} \cdot \frac{\sqrt{x}}{1}}{\sqrt{x + 1} + \frac{\sqrt{x}}{1}}} \cdot \frac{1}{\sqrt{x} \cdot \sqrt{x + 1}} \]
              10. metadata-evalN/A

                \[\leadsto \frac{\sqrt{x + 1} \cdot \sqrt{x + 1} - \frac{\sqrt{x}}{1} \cdot \frac{\sqrt{x}}{1}}{\sqrt{x + 1} + \frac{\sqrt{x}}{1}} \cdot \frac{\color{blue}{1 \cdot 1}}{\sqrt{x} \cdot \sqrt{x + 1}} \]
              11. frac-timesN/A

                \[\leadsto \frac{\sqrt{x + 1} \cdot \sqrt{x + 1} - \frac{\sqrt{x}}{1} \cdot \frac{\sqrt{x}}{1}}{\sqrt{x + 1} + \frac{\sqrt{x}}{1}} \cdot \color{blue}{\left(\frac{1}{\sqrt{x}} \cdot \frac{1}{\sqrt{x + 1}}\right)} \]
              12. lift-/.f64N/A

                \[\leadsto \frac{\sqrt{x + 1} \cdot \sqrt{x + 1} - \frac{\sqrt{x}}{1} \cdot \frac{\sqrt{x}}{1}}{\sqrt{x + 1} + \frac{\sqrt{x}}{1}} \cdot \left(\color{blue}{\frac{1}{\sqrt{x}}} \cdot \frac{1}{\sqrt{x + 1}}\right) \]
              13. frac-2negN/A

                \[\leadsto \frac{\sqrt{x + 1} \cdot \sqrt{x + 1} - \frac{\sqrt{x}}{1} \cdot \frac{\sqrt{x}}{1}}{\sqrt{x + 1} + \frac{\sqrt{x}}{1}} \cdot \left(\frac{1}{\sqrt{x}} \cdot \color{blue}{\frac{\mathsf{neg}\left(1\right)}{\mathsf{neg}\left(\sqrt{x + 1}\right)}}\right) \]
              14. metadata-evalN/A

                \[\leadsto \frac{\sqrt{x + 1} \cdot \sqrt{x + 1} - \frac{\sqrt{x}}{1} \cdot \frac{\sqrt{x}}{1}}{\sqrt{x + 1} + \frac{\sqrt{x}}{1}} \cdot \left(\frac{1}{\sqrt{x}} \cdot \frac{\color{blue}{-1}}{\mathsf{neg}\left(\sqrt{x + 1}\right)}\right) \]
              15. associate-*r/N/A

                \[\leadsto \frac{\sqrt{x + 1} \cdot \sqrt{x + 1} - \frac{\sqrt{x}}{1} \cdot \frac{\sqrt{x}}{1}}{\sqrt{x + 1} + \frac{\sqrt{x}}{1}} \cdot \color{blue}{\frac{\frac{1}{\sqrt{x}} \cdot -1}{\mathsf{neg}\left(\sqrt{x + 1}\right)}} \]
            4. Applied rewrites41.1%

              \[\leadsto \color{blue}{\frac{\left(\left(x + 1\right) - x\right) \cdot \frac{-1}{\sqrt{x}}}{\left(\sqrt{x} + \sqrt{x + 1}\right) \cdot \left(-\sqrt{x + 1}\right)}} \]
            5. Taylor expanded in x around 0

              \[\leadsto \frac{\color{blue}{1} \cdot \frac{-1}{\sqrt{x}}}{\left(\sqrt{x} + \sqrt{x + 1}\right) \cdot \left(-\sqrt{x + 1}\right)} \]
            6. Step-by-step derivation
              1. Applied rewrites99.3%

                \[\leadsto \frac{\color{blue}{1} \cdot \frac{-1}{\sqrt{x}}}{\left(\sqrt{x} + \sqrt{x + 1}\right) \cdot \left(-\sqrt{x + 1}\right)} \]
              2. Step-by-step derivation
                1. lift-/.f64N/A

                  \[\leadsto \color{blue}{\frac{1 \cdot \frac{-1}{\sqrt{x}}}{\left(\sqrt{x} + \sqrt{x + 1}\right) \cdot \left(-\sqrt{x + 1}\right)}} \]
                2. lift-*.f64N/A

                  \[\leadsto \frac{1 \cdot \frac{-1}{\sqrt{x}}}{\color{blue}{\left(\sqrt{x} + \sqrt{x + 1}\right) \cdot \left(-\sqrt{x + 1}\right)}} \]
                3. associate-/r*N/A

                  \[\leadsto \color{blue}{\frac{\frac{1 \cdot \frac{-1}{\sqrt{x}}}{\sqrt{x} + \sqrt{x + 1}}}{-\sqrt{x + 1}}} \]
                4. lower-/.f64N/A

                  \[\leadsto \color{blue}{\frac{\frac{1 \cdot \frac{-1}{\sqrt{x}}}{\sqrt{x} + \sqrt{x + 1}}}{-\sqrt{x + 1}}} \]
              3. Applied rewrites99.7%

                \[\leadsto \color{blue}{\frac{\frac{1 \cdot -1}{\mathsf{hypot}\left(\sqrt{x}, x\right) + x}}{-\sqrt{1 + x}}} \]
              4. Taylor expanded in x around inf

                \[\leadsto \frac{\frac{1 \cdot -1}{\color{blue}{x \cdot \left(2 + \frac{1}{2} \cdot \frac{1}{x}\right)}}}{-\sqrt{1 + x}} \]
              5. Step-by-step derivation
                1. *-commutativeN/A

                  \[\leadsto \frac{\frac{1 \cdot -1}{\color{blue}{\left(2 + \frac{1}{2} \cdot \frac{1}{x}\right) \cdot x}}}{-\sqrt{1 + x}} \]
                2. lower-*.f64N/A

                  \[\leadsto \frac{\frac{1 \cdot -1}{\color{blue}{\left(2 + \frac{1}{2} \cdot \frac{1}{x}\right) \cdot x}}}{-\sqrt{1 + x}} \]
                3. lower-+.f64N/A

                  \[\leadsto \frac{\frac{1 \cdot -1}{\color{blue}{\left(2 + \frac{1}{2} \cdot \frac{1}{x}\right)} \cdot x}}{-\sqrt{1 + x}} \]
                4. associate-*r/N/A

                  \[\leadsto \frac{\frac{1 \cdot -1}{\left(2 + \color{blue}{\frac{\frac{1}{2} \cdot 1}{x}}\right) \cdot x}}{-\sqrt{1 + x}} \]
                5. metadata-evalN/A

                  \[\leadsto \frac{\frac{1 \cdot -1}{\left(2 + \frac{\color{blue}{\frac{1}{2}}}{x}\right) \cdot x}}{-\sqrt{1 + x}} \]
                6. lower-/.f6499.0

                  \[\leadsto \frac{\frac{1 \cdot -1}{\left(2 + \color{blue}{\frac{0.5}{x}}\right) \cdot x}}{-\sqrt{1 + x}} \]
              6. Applied rewrites99.0%

                \[\leadsto \frac{\frac{1 \cdot -1}{\color{blue}{\left(2 + \frac{0.5}{x}\right) \cdot x}}}{-\sqrt{1 + x}} \]
              7. Final simplification99.0%

                \[\leadsto \frac{\frac{1}{\left(\frac{0.5}{x} + 2\right) \cdot x}}{\sqrt{1 + x}} \]
              8. Add Preprocessing

              Alternative 7: 98.8% accurate, 0.9× speedup?

              \[\begin{array}{l} \\ \frac{\frac{\frac{0.125}{x} - 0.5}{x}}{-\sqrt{1 + x}} \end{array} \]
              (FPCore (x)
               :precision binary64
               (/ (/ (- (/ 0.125 x) 0.5) x) (- (sqrt (+ 1.0 x)))))
              double code(double x) {
              	return (((0.125 / x) - 0.5) / x) / -sqrt((1.0 + x));
              }
              
              real(8) function code(x)
                  real(8), intent (in) :: x
                  code = (((0.125d0 / x) - 0.5d0) / x) / -sqrt((1.0d0 + x))
              end function
              
              public static double code(double x) {
              	return (((0.125 / x) - 0.5) / x) / -Math.sqrt((1.0 + x));
              }
              
              def code(x):
              	return (((0.125 / x) - 0.5) / x) / -math.sqrt((1.0 + x))
              
              function code(x)
              	return Float64(Float64(Float64(Float64(0.125 / x) - 0.5) / x) / Float64(-sqrt(Float64(1.0 + x))))
              end
              
              function tmp = code(x)
              	tmp = (((0.125 / x) - 0.5) / x) / -sqrt((1.0 + x));
              end
              
              code[x_] := N[(N[(N[(N[(0.125 / x), $MachinePrecision] - 0.5), $MachinePrecision] / x), $MachinePrecision] / (-N[Sqrt[N[(1.0 + x), $MachinePrecision]], $MachinePrecision])), $MachinePrecision]
              
              \begin{array}{l}
              
              \\
              \frac{\frac{\frac{0.125}{x} - 0.5}{x}}{-\sqrt{1 + x}}
              \end{array}
              
              Derivation
              1. Initial program 39.1%

                \[\frac{1}{\sqrt{x}} - \frac{1}{\sqrt{x + 1}} \]
              2. Add Preprocessing
              3. Step-by-step derivation
                1. lift--.f64N/A

                  \[\leadsto \color{blue}{\frac{1}{\sqrt{x}} - \frac{1}{\sqrt{x + 1}}} \]
                2. lift-/.f64N/A

                  \[\leadsto \color{blue}{\frac{1}{\sqrt{x}}} - \frac{1}{\sqrt{x + 1}} \]
                3. lift-/.f64N/A

                  \[\leadsto \frac{1}{\sqrt{x}} - \color{blue}{\frac{1}{\sqrt{x + 1}}} \]
                4. frac-subN/A

                  \[\leadsto \color{blue}{\frac{1 \cdot \sqrt{x + 1} - \sqrt{x} \cdot 1}{\sqrt{x} \cdot \sqrt{x + 1}}} \]
                5. div-invN/A

                  \[\leadsto \color{blue}{\left(1 \cdot \sqrt{x + 1} - \sqrt{x} \cdot 1\right) \cdot \frac{1}{\sqrt{x} \cdot \sqrt{x + 1}}} \]
                6. metadata-evalN/A

                  \[\leadsto \left(1 \cdot \sqrt{x + 1} - \sqrt{x} \cdot \color{blue}{\frac{1}{1}}\right) \cdot \frac{1}{\sqrt{x} \cdot \sqrt{x + 1}} \]
                7. div-invN/A

                  \[\leadsto \left(1 \cdot \sqrt{x + 1} - \color{blue}{\frac{\sqrt{x}}{1}}\right) \cdot \frac{1}{\sqrt{x} \cdot \sqrt{x + 1}} \]
                8. *-lft-identityN/A

                  \[\leadsto \left(\color{blue}{\sqrt{x + 1}} - \frac{\sqrt{x}}{1}\right) \cdot \frac{1}{\sqrt{x} \cdot \sqrt{x + 1}} \]
                9. flip--N/A

                  \[\leadsto \color{blue}{\frac{\sqrt{x + 1} \cdot \sqrt{x + 1} - \frac{\sqrt{x}}{1} \cdot \frac{\sqrt{x}}{1}}{\sqrt{x + 1} + \frac{\sqrt{x}}{1}}} \cdot \frac{1}{\sqrt{x} \cdot \sqrt{x + 1}} \]
                10. metadata-evalN/A

                  \[\leadsto \frac{\sqrt{x + 1} \cdot \sqrt{x + 1} - \frac{\sqrt{x}}{1} \cdot \frac{\sqrt{x}}{1}}{\sqrt{x + 1} + \frac{\sqrt{x}}{1}} \cdot \frac{\color{blue}{1 \cdot 1}}{\sqrt{x} \cdot \sqrt{x + 1}} \]
                11. frac-timesN/A

                  \[\leadsto \frac{\sqrt{x + 1} \cdot \sqrt{x + 1} - \frac{\sqrt{x}}{1} \cdot \frac{\sqrt{x}}{1}}{\sqrt{x + 1} + \frac{\sqrt{x}}{1}} \cdot \color{blue}{\left(\frac{1}{\sqrt{x}} \cdot \frac{1}{\sqrt{x + 1}}\right)} \]
                12. lift-/.f64N/A

                  \[\leadsto \frac{\sqrt{x + 1} \cdot \sqrt{x + 1} - \frac{\sqrt{x}}{1} \cdot \frac{\sqrt{x}}{1}}{\sqrt{x + 1} + \frac{\sqrt{x}}{1}} \cdot \left(\color{blue}{\frac{1}{\sqrt{x}}} \cdot \frac{1}{\sqrt{x + 1}}\right) \]
                13. frac-2negN/A

                  \[\leadsto \frac{\sqrt{x + 1} \cdot \sqrt{x + 1} - \frac{\sqrt{x}}{1} \cdot \frac{\sqrt{x}}{1}}{\sqrt{x + 1} + \frac{\sqrt{x}}{1}} \cdot \left(\frac{1}{\sqrt{x}} \cdot \color{blue}{\frac{\mathsf{neg}\left(1\right)}{\mathsf{neg}\left(\sqrt{x + 1}\right)}}\right) \]
                14. metadata-evalN/A

                  \[\leadsto \frac{\sqrt{x + 1} \cdot \sqrt{x + 1} - \frac{\sqrt{x}}{1} \cdot \frac{\sqrt{x}}{1}}{\sqrt{x + 1} + \frac{\sqrt{x}}{1}} \cdot \left(\frac{1}{\sqrt{x}} \cdot \frac{\color{blue}{-1}}{\mathsf{neg}\left(\sqrt{x + 1}\right)}\right) \]
                15. associate-*r/N/A

                  \[\leadsto \frac{\sqrt{x + 1} \cdot \sqrt{x + 1} - \frac{\sqrt{x}}{1} \cdot \frac{\sqrt{x}}{1}}{\sqrt{x + 1} + \frac{\sqrt{x}}{1}} \cdot \color{blue}{\frac{\frac{1}{\sqrt{x}} \cdot -1}{\mathsf{neg}\left(\sqrt{x + 1}\right)}} \]
              4. Applied rewrites41.1%

                \[\leadsto \color{blue}{\frac{\left(\left(x + 1\right) - x\right) \cdot \frac{-1}{\sqrt{x}}}{\left(\sqrt{x} + \sqrt{x + 1}\right) \cdot \left(-\sqrt{x + 1}\right)}} \]
              5. Taylor expanded in x around 0

                \[\leadsto \frac{\color{blue}{1} \cdot \frac{-1}{\sqrt{x}}}{\left(\sqrt{x} + \sqrt{x + 1}\right) \cdot \left(-\sqrt{x + 1}\right)} \]
              6. Step-by-step derivation
                1. Applied rewrites99.3%

                  \[\leadsto \frac{\color{blue}{1} \cdot \frac{-1}{\sqrt{x}}}{\left(\sqrt{x} + \sqrt{x + 1}\right) \cdot \left(-\sqrt{x + 1}\right)} \]
                2. Step-by-step derivation
                  1. lift-/.f64N/A

                    \[\leadsto \color{blue}{\frac{1 \cdot \frac{-1}{\sqrt{x}}}{\left(\sqrt{x} + \sqrt{x + 1}\right) \cdot \left(-\sqrt{x + 1}\right)}} \]
                  2. lift-*.f64N/A

                    \[\leadsto \frac{1 \cdot \frac{-1}{\sqrt{x}}}{\color{blue}{\left(\sqrt{x} + \sqrt{x + 1}\right) \cdot \left(-\sqrt{x + 1}\right)}} \]
                  3. associate-/r*N/A

                    \[\leadsto \color{blue}{\frac{\frac{1 \cdot \frac{-1}{\sqrt{x}}}{\sqrt{x} + \sqrt{x + 1}}}{-\sqrt{x + 1}}} \]
                  4. lower-/.f64N/A

                    \[\leadsto \color{blue}{\frac{\frac{1 \cdot \frac{-1}{\sqrt{x}}}{\sqrt{x} + \sqrt{x + 1}}}{-\sqrt{x + 1}}} \]
                3. Applied rewrites99.7%

                  \[\leadsto \color{blue}{\frac{\frac{1 \cdot -1}{\mathsf{hypot}\left(\sqrt{x}, x\right) + x}}{-\sqrt{1 + x}}} \]
                4. Taylor expanded in x around inf

                  \[\leadsto \frac{\color{blue}{\frac{\frac{1}{8} \cdot \frac{1}{x} - \frac{1}{2}}{x}}}{-\sqrt{1 + x}} \]
                5. Step-by-step derivation
                  1. lower-/.f64N/A

                    \[\leadsto \frac{\color{blue}{\frac{\frac{1}{8} \cdot \frac{1}{x} - \frac{1}{2}}{x}}}{-\sqrt{1 + x}} \]
                  2. lower--.f64N/A

                    \[\leadsto \frac{\frac{\color{blue}{\frac{1}{8} \cdot \frac{1}{x} - \frac{1}{2}}}{x}}{-\sqrt{1 + x}} \]
                  3. associate-*r/N/A

                    \[\leadsto \frac{\frac{\color{blue}{\frac{\frac{1}{8} \cdot 1}{x}} - \frac{1}{2}}{x}}{-\sqrt{1 + x}} \]
                  4. metadata-evalN/A

                    \[\leadsto \frac{\frac{\frac{\color{blue}{\frac{1}{8}}}{x} - \frac{1}{2}}{x}}{-\sqrt{1 + x}} \]
                  5. lower-/.f6498.9

                    \[\leadsto \frac{\frac{\color{blue}{\frac{0.125}{x}} - 0.5}{x}}{-\sqrt{1 + x}} \]
                6. Applied rewrites98.9%

                  \[\leadsto \frac{\color{blue}{\frac{\frac{0.125}{x} - 0.5}{x}}}{-\sqrt{1 + x}} \]
                7. Add Preprocessing

                Alternative 8: 98.7% accurate, 1.0× speedup?

                \[\begin{array}{l} \\ \frac{\frac{0.5 - \frac{0.375}{x}}{x}}{\sqrt{x}} \end{array} \]
                (FPCore (x) :precision binary64 (/ (/ (- 0.5 (/ 0.375 x)) x) (sqrt x)))
                double code(double x) {
                	return ((0.5 - (0.375 / x)) / x) / sqrt(x);
                }
                
                real(8) function code(x)
                    real(8), intent (in) :: x
                    code = ((0.5d0 - (0.375d0 / x)) / x) / sqrt(x)
                end function
                
                public static double code(double x) {
                	return ((0.5 - (0.375 / x)) / x) / Math.sqrt(x);
                }
                
                def code(x):
                	return ((0.5 - (0.375 / x)) / x) / math.sqrt(x)
                
                function code(x)
                	return Float64(Float64(Float64(0.5 - Float64(0.375 / x)) / x) / sqrt(x))
                end
                
                function tmp = code(x)
                	tmp = ((0.5 - (0.375 / x)) / x) / sqrt(x);
                end
                
                code[x_] := N[(N[(N[(0.5 - N[(0.375 / x), $MachinePrecision]), $MachinePrecision] / x), $MachinePrecision] / N[Sqrt[x], $MachinePrecision]), $MachinePrecision]
                
                \begin{array}{l}
                
                \\
                \frac{\frac{0.5 - \frac{0.375}{x}}{x}}{\sqrt{x}}
                \end{array}
                
                Derivation
                1. Initial program 39.1%

                  \[\frac{1}{\sqrt{x}} - \frac{1}{\sqrt{x + 1}} \]
                2. Add Preprocessing
                3. Step-by-step derivation
                  1. lift--.f64N/A

                    \[\leadsto \color{blue}{\frac{1}{\sqrt{x}} - \frac{1}{\sqrt{x + 1}}} \]
                  2. lift-/.f64N/A

                    \[\leadsto \color{blue}{\frac{1}{\sqrt{x}}} - \frac{1}{\sqrt{x + 1}} \]
                  3. clear-numN/A

                    \[\leadsto \color{blue}{\frac{1}{\frac{\sqrt{x}}{1}}} - \frac{1}{\sqrt{x + 1}} \]
                  4. lift-/.f64N/A

                    \[\leadsto \frac{1}{\frac{\sqrt{x}}{1}} - \color{blue}{\frac{1}{\sqrt{x + 1}}} \]
                  5. frac-subN/A

                    \[\leadsto \color{blue}{\frac{1 \cdot \sqrt{x + 1} - \frac{\sqrt{x}}{1} \cdot 1}{\frac{\sqrt{x}}{1} \cdot \sqrt{x + 1}}} \]
                  6. div-invN/A

                    \[\leadsto \frac{1 \cdot \sqrt{x + 1} - \color{blue}{\left(\sqrt{x} \cdot \frac{1}{1}\right)} \cdot 1}{\frac{\sqrt{x}}{1} \cdot \sqrt{x + 1}} \]
                  7. metadata-evalN/A

                    \[\leadsto \frac{1 \cdot \sqrt{x + 1} - \left(\sqrt{x} \cdot \color{blue}{1}\right) \cdot 1}{\frac{\sqrt{x}}{1} \cdot \sqrt{x + 1}} \]
                  8. *-rgt-identityN/A

                    \[\leadsto \frac{1 \cdot \sqrt{x + 1} - \color{blue}{\sqrt{x}} \cdot 1}{\frac{\sqrt{x}}{1} \cdot \sqrt{x + 1}} \]
                  9. *-commutativeN/A

                    \[\leadsto \frac{1 \cdot \sqrt{x + 1} - \sqrt{x} \cdot 1}{\color{blue}{\sqrt{x + 1} \cdot \frac{\sqrt{x}}{1}}} \]
                  10. associate-/r*N/A

                    \[\leadsto \color{blue}{\frac{\frac{1 \cdot \sqrt{x + 1} - \sqrt{x} \cdot 1}{\sqrt{x + 1}}}{\frac{\sqrt{x}}{1}}} \]
                  11. lower-/.f64N/A

                    \[\leadsto \color{blue}{\frac{\frac{1 \cdot \sqrt{x + 1} - \sqrt{x} \cdot 1}{\sqrt{x + 1}}}{\frac{\sqrt{x}}{1}}} \]
                4. Applied rewrites39.2%

                  \[\leadsto \color{blue}{\frac{\frac{\sqrt{x + 1} - \sqrt{x}}{\sqrt{x + 1}}}{\sqrt{x}}} \]
                5. Taylor expanded in x around inf

                  \[\leadsto \frac{\color{blue}{\frac{\left(\frac{1}{2} + \frac{1}{4} \cdot \frac{1}{{x}^{2}}\right) - \left(\frac{\frac{1}{8}}{x} + \frac{\frac{1}{4}}{x}\right)}{x}}}{\sqrt{x}} \]
                6. Step-by-step derivation
                  1. lower-/.f64N/A

                    \[\leadsto \frac{\color{blue}{\frac{\left(\frac{1}{2} + \frac{1}{4} \cdot \frac{1}{{x}^{2}}\right) - \left(\frac{\frac{1}{8}}{x} + \frac{\frac{1}{4}}{x}\right)}{x}}}{\sqrt{x}} \]
                  2. lower--.f64N/A

                    \[\leadsto \frac{\frac{\color{blue}{\left(\frac{1}{2} + \frac{1}{4} \cdot \frac{1}{{x}^{2}}\right) - \left(\frac{\frac{1}{8}}{x} + \frac{\frac{1}{4}}{x}\right)}}{x}}{\sqrt{x}} \]
                  3. +-commutativeN/A

                    \[\leadsto \frac{\frac{\color{blue}{\left(\frac{1}{4} \cdot \frac{1}{{x}^{2}} + \frac{1}{2}\right)} - \left(\frac{\frac{1}{8}}{x} + \frac{\frac{1}{4}}{x}\right)}{x}}{\sqrt{x}} \]
                  4. lower-+.f64N/A

                    \[\leadsto \frac{\frac{\color{blue}{\left(\frac{1}{4} \cdot \frac{1}{{x}^{2}} + \frac{1}{2}\right)} - \left(\frac{\frac{1}{8}}{x} + \frac{\frac{1}{4}}{x}\right)}{x}}{\sqrt{x}} \]
                  5. associate-*r/N/A

                    \[\leadsto \frac{\frac{\left(\color{blue}{\frac{\frac{1}{4} \cdot 1}{{x}^{2}}} + \frac{1}{2}\right) - \left(\frac{\frac{1}{8}}{x} + \frac{\frac{1}{4}}{x}\right)}{x}}{\sqrt{x}} \]
                  6. metadata-evalN/A

                    \[\leadsto \frac{\frac{\left(\frac{\color{blue}{\frac{1}{4}}}{{x}^{2}} + \frac{1}{2}\right) - \left(\frac{\frac{1}{8}}{x} + \frac{\frac{1}{4}}{x}\right)}{x}}{\sqrt{x}} \]
                  7. lower-/.f64N/A

                    \[\leadsto \frac{\frac{\left(\color{blue}{\frac{\frac{1}{4}}{{x}^{2}}} + \frac{1}{2}\right) - \left(\frac{\frac{1}{8}}{x} + \frac{\frac{1}{4}}{x}\right)}{x}}{\sqrt{x}} \]
                  8. unpow2N/A

                    \[\leadsto \frac{\frac{\left(\frac{\frac{1}{4}}{\color{blue}{x \cdot x}} + \frac{1}{2}\right) - \left(\frac{\frac{1}{8}}{x} + \frac{\frac{1}{4}}{x}\right)}{x}}{\sqrt{x}} \]
                  9. lower-*.f64N/A

                    \[\leadsto \frac{\frac{\left(\frac{\frac{1}{4}}{\color{blue}{x \cdot x}} + \frac{1}{2}\right) - \left(\frac{\frac{1}{8}}{x} + \frac{\frac{1}{4}}{x}\right)}{x}}{\sqrt{x}} \]
                  10. div-add-revN/A

                    \[\leadsto \frac{\frac{\left(\frac{\frac{1}{4}}{x \cdot x} + \frac{1}{2}\right) - \color{blue}{\frac{\frac{1}{8} + \frac{1}{4}}{x}}}{x}}{\sqrt{x}} \]
                  11. metadata-evalN/A

                    \[\leadsto \frac{\frac{\left(\frac{\frac{1}{4}}{x \cdot x} + \frac{1}{2}\right) - \frac{\color{blue}{\frac{3}{8}}}{x}}{x}}{\sqrt{x}} \]
                  12. lower-/.f6498.9

                    \[\leadsto \frac{\frac{\left(\frac{0.25}{x \cdot x} + 0.5\right) - \color{blue}{\frac{0.375}{x}}}{x}}{\sqrt{x}} \]
                7. Applied rewrites98.9%

                  \[\leadsto \frac{\color{blue}{\frac{\left(\frac{0.25}{x \cdot x} + 0.5\right) - \frac{0.375}{x}}{x}}}{\sqrt{x}} \]
                8. Taylor expanded in x around inf

                  \[\leadsto \frac{\frac{\frac{1}{2} - \frac{3}{8} \cdot \frac{1}{x}}{x}}{\sqrt{x}} \]
                9. Step-by-step derivation
                  1. Applied rewrites98.8%

                    \[\leadsto \frac{\frac{0.5 - \frac{0.375}{x}}{x}}{\sqrt{x}} \]
                  2. Add Preprocessing

                  Alternative 9: 97.9% accurate, 1.3× speedup?

                  \[\begin{array}{l} \\ \frac{\frac{-0.5}{x}}{-\sqrt{1 + x}} \end{array} \]
                  (FPCore (x) :precision binary64 (/ (/ -0.5 x) (- (sqrt (+ 1.0 x)))))
                  double code(double x) {
                  	return (-0.5 / x) / -sqrt((1.0 + x));
                  }
                  
                  real(8) function code(x)
                      real(8), intent (in) :: x
                      code = ((-0.5d0) / x) / -sqrt((1.0d0 + x))
                  end function
                  
                  public static double code(double x) {
                  	return (-0.5 / x) / -Math.sqrt((1.0 + x));
                  }
                  
                  def code(x):
                  	return (-0.5 / x) / -math.sqrt((1.0 + x))
                  
                  function code(x)
                  	return Float64(Float64(-0.5 / x) / Float64(-sqrt(Float64(1.0 + x))))
                  end
                  
                  function tmp = code(x)
                  	tmp = (-0.5 / x) / -sqrt((1.0 + x));
                  end
                  
                  code[x_] := N[(N[(-0.5 / x), $MachinePrecision] / (-N[Sqrt[N[(1.0 + x), $MachinePrecision]], $MachinePrecision])), $MachinePrecision]
                  
                  \begin{array}{l}
                  
                  \\
                  \frac{\frac{-0.5}{x}}{-\sqrt{1 + x}}
                  \end{array}
                  
                  Derivation
                  1. Initial program 39.1%

                    \[\frac{1}{\sqrt{x}} - \frac{1}{\sqrt{x + 1}} \]
                  2. Add Preprocessing
                  3. Step-by-step derivation
                    1. lift--.f64N/A

                      \[\leadsto \color{blue}{\frac{1}{\sqrt{x}} - \frac{1}{\sqrt{x + 1}}} \]
                    2. lift-/.f64N/A

                      \[\leadsto \color{blue}{\frac{1}{\sqrt{x}}} - \frac{1}{\sqrt{x + 1}} \]
                    3. lift-/.f64N/A

                      \[\leadsto \frac{1}{\sqrt{x}} - \color{blue}{\frac{1}{\sqrt{x + 1}}} \]
                    4. frac-subN/A

                      \[\leadsto \color{blue}{\frac{1 \cdot \sqrt{x + 1} - \sqrt{x} \cdot 1}{\sqrt{x} \cdot \sqrt{x + 1}}} \]
                    5. div-invN/A

                      \[\leadsto \color{blue}{\left(1 \cdot \sqrt{x + 1} - \sqrt{x} \cdot 1\right) \cdot \frac{1}{\sqrt{x} \cdot \sqrt{x + 1}}} \]
                    6. metadata-evalN/A

                      \[\leadsto \left(1 \cdot \sqrt{x + 1} - \sqrt{x} \cdot \color{blue}{\frac{1}{1}}\right) \cdot \frac{1}{\sqrt{x} \cdot \sqrt{x + 1}} \]
                    7. div-invN/A

                      \[\leadsto \left(1 \cdot \sqrt{x + 1} - \color{blue}{\frac{\sqrt{x}}{1}}\right) \cdot \frac{1}{\sqrt{x} \cdot \sqrt{x + 1}} \]
                    8. *-lft-identityN/A

                      \[\leadsto \left(\color{blue}{\sqrt{x + 1}} - \frac{\sqrt{x}}{1}\right) \cdot \frac{1}{\sqrt{x} \cdot \sqrt{x + 1}} \]
                    9. flip--N/A

                      \[\leadsto \color{blue}{\frac{\sqrt{x + 1} \cdot \sqrt{x + 1} - \frac{\sqrt{x}}{1} \cdot \frac{\sqrt{x}}{1}}{\sqrt{x + 1} + \frac{\sqrt{x}}{1}}} \cdot \frac{1}{\sqrt{x} \cdot \sqrt{x + 1}} \]
                    10. metadata-evalN/A

                      \[\leadsto \frac{\sqrt{x + 1} \cdot \sqrt{x + 1} - \frac{\sqrt{x}}{1} \cdot \frac{\sqrt{x}}{1}}{\sqrt{x + 1} + \frac{\sqrt{x}}{1}} \cdot \frac{\color{blue}{1 \cdot 1}}{\sqrt{x} \cdot \sqrt{x + 1}} \]
                    11. frac-timesN/A

                      \[\leadsto \frac{\sqrt{x + 1} \cdot \sqrt{x + 1} - \frac{\sqrt{x}}{1} \cdot \frac{\sqrt{x}}{1}}{\sqrt{x + 1} + \frac{\sqrt{x}}{1}} \cdot \color{blue}{\left(\frac{1}{\sqrt{x}} \cdot \frac{1}{\sqrt{x + 1}}\right)} \]
                    12. lift-/.f64N/A

                      \[\leadsto \frac{\sqrt{x + 1} \cdot \sqrt{x + 1} - \frac{\sqrt{x}}{1} \cdot \frac{\sqrt{x}}{1}}{\sqrt{x + 1} + \frac{\sqrt{x}}{1}} \cdot \left(\color{blue}{\frac{1}{\sqrt{x}}} \cdot \frac{1}{\sqrt{x + 1}}\right) \]
                    13. frac-2negN/A

                      \[\leadsto \frac{\sqrt{x + 1} \cdot \sqrt{x + 1} - \frac{\sqrt{x}}{1} \cdot \frac{\sqrt{x}}{1}}{\sqrt{x + 1} + \frac{\sqrt{x}}{1}} \cdot \left(\frac{1}{\sqrt{x}} \cdot \color{blue}{\frac{\mathsf{neg}\left(1\right)}{\mathsf{neg}\left(\sqrt{x + 1}\right)}}\right) \]
                    14. metadata-evalN/A

                      \[\leadsto \frac{\sqrt{x + 1} \cdot \sqrt{x + 1} - \frac{\sqrt{x}}{1} \cdot \frac{\sqrt{x}}{1}}{\sqrt{x + 1} + \frac{\sqrt{x}}{1}} \cdot \left(\frac{1}{\sqrt{x}} \cdot \frac{\color{blue}{-1}}{\mathsf{neg}\left(\sqrt{x + 1}\right)}\right) \]
                    15. associate-*r/N/A

                      \[\leadsto \frac{\sqrt{x + 1} \cdot \sqrt{x + 1} - \frac{\sqrt{x}}{1} \cdot \frac{\sqrt{x}}{1}}{\sqrt{x + 1} + \frac{\sqrt{x}}{1}} \cdot \color{blue}{\frac{\frac{1}{\sqrt{x}} \cdot -1}{\mathsf{neg}\left(\sqrt{x + 1}\right)}} \]
                  4. Applied rewrites41.1%

                    \[\leadsto \color{blue}{\frac{\left(\left(x + 1\right) - x\right) \cdot \frac{-1}{\sqrt{x}}}{\left(\sqrt{x} + \sqrt{x + 1}\right) \cdot \left(-\sqrt{x + 1}\right)}} \]
                  5. Taylor expanded in x around 0

                    \[\leadsto \frac{\color{blue}{1} \cdot \frac{-1}{\sqrt{x}}}{\left(\sqrt{x} + \sqrt{x + 1}\right) \cdot \left(-\sqrt{x + 1}\right)} \]
                  6. Step-by-step derivation
                    1. Applied rewrites99.3%

                      \[\leadsto \frac{\color{blue}{1} \cdot \frac{-1}{\sqrt{x}}}{\left(\sqrt{x} + \sqrt{x + 1}\right) \cdot \left(-\sqrt{x + 1}\right)} \]
                    2. Step-by-step derivation
                      1. lift-/.f64N/A

                        \[\leadsto \color{blue}{\frac{1 \cdot \frac{-1}{\sqrt{x}}}{\left(\sqrt{x} + \sqrt{x + 1}\right) \cdot \left(-\sqrt{x + 1}\right)}} \]
                      2. lift-*.f64N/A

                        \[\leadsto \frac{1 \cdot \frac{-1}{\sqrt{x}}}{\color{blue}{\left(\sqrt{x} + \sqrt{x + 1}\right) \cdot \left(-\sqrt{x + 1}\right)}} \]
                      3. associate-/r*N/A

                        \[\leadsto \color{blue}{\frac{\frac{1 \cdot \frac{-1}{\sqrt{x}}}{\sqrt{x} + \sqrt{x + 1}}}{-\sqrt{x + 1}}} \]
                      4. lower-/.f64N/A

                        \[\leadsto \color{blue}{\frac{\frac{1 \cdot \frac{-1}{\sqrt{x}}}{\sqrt{x} + \sqrt{x + 1}}}{-\sqrt{x + 1}}} \]
                    3. Applied rewrites99.7%

                      \[\leadsto \color{blue}{\frac{\frac{1 \cdot -1}{\mathsf{hypot}\left(\sqrt{x}, x\right) + x}}{-\sqrt{1 + x}}} \]
                    4. Taylor expanded in x around inf

                      \[\leadsto \frac{\color{blue}{\frac{\frac{-1}{2}}{x}}}{-\sqrt{1 + x}} \]
                    5. Step-by-step derivation
                      1. lower-/.f6497.5

                        \[\leadsto \frac{\color{blue}{\frac{-0.5}{x}}}{-\sqrt{1 + x}} \]
                    6. Applied rewrites97.5%

                      \[\leadsto \frac{\color{blue}{\frac{-0.5}{x}}}{-\sqrt{1 + x}} \]
                    7. Add Preprocessing

                    Alternative 10: 97.8% accurate, 1.5× speedup?

                    \[\begin{array}{l} \\ \frac{\frac{0.5}{x}}{\sqrt{x}} \end{array} \]
                    (FPCore (x) :precision binary64 (/ (/ 0.5 x) (sqrt x)))
                    double code(double x) {
                    	return (0.5 / x) / sqrt(x);
                    }
                    
                    real(8) function code(x)
                        real(8), intent (in) :: x
                        code = (0.5d0 / x) / sqrt(x)
                    end function
                    
                    public static double code(double x) {
                    	return (0.5 / x) / Math.sqrt(x);
                    }
                    
                    def code(x):
                    	return (0.5 / x) / math.sqrt(x)
                    
                    function code(x)
                    	return Float64(Float64(0.5 / x) / sqrt(x))
                    end
                    
                    function tmp = code(x)
                    	tmp = (0.5 / x) / sqrt(x);
                    end
                    
                    code[x_] := N[(N[(0.5 / x), $MachinePrecision] / N[Sqrt[x], $MachinePrecision]), $MachinePrecision]
                    
                    \begin{array}{l}
                    
                    \\
                    \frac{\frac{0.5}{x}}{\sqrt{x}}
                    \end{array}
                    
                    Derivation
                    1. Initial program 39.1%

                      \[\frac{1}{\sqrt{x}} - \frac{1}{\sqrt{x + 1}} \]
                    2. Add Preprocessing
                    3. Step-by-step derivation
                      1. lift--.f64N/A

                        \[\leadsto \color{blue}{\frac{1}{\sqrt{x}} - \frac{1}{\sqrt{x + 1}}} \]
                      2. lift-/.f64N/A

                        \[\leadsto \color{blue}{\frac{1}{\sqrt{x}}} - \frac{1}{\sqrt{x + 1}} \]
                      3. clear-numN/A

                        \[\leadsto \color{blue}{\frac{1}{\frac{\sqrt{x}}{1}}} - \frac{1}{\sqrt{x + 1}} \]
                      4. lift-/.f64N/A

                        \[\leadsto \frac{1}{\frac{\sqrt{x}}{1}} - \color{blue}{\frac{1}{\sqrt{x + 1}}} \]
                      5. frac-subN/A

                        \[\leadsto \color{blue}{\frac{1 \cdot \sqrt{x + 1} - \frac{\sqrt{x}}{1} \cdot 1}{\frac{\sqrt{x}}{1} \cdot \sqrt{x + 1}}} \]
                      6. div-invN/A

                        \[\leadsto \frac{1 \cdot \sqrt{x + 1} - \color{blue}{\left(\sqrt{x} \cdot \frac{1}{1}\right)} \cdot 1}{\frac{\sqrt{x}}{1} \cdot \sqrt{x + 1}} \]
                      7. metadata-evalN/A

                        \[\leadsto \frac{1 \cdot \sqrt{x + 1} - \left(\sqrt{x} \cdot \color{blue}{1}\right) \cdot 1}{\frac{\sqrt{x}}{1} \cdot \sqrt{x + 1}} \]
                      8. *-rgt-identityN/A

                        \[\leadsto \frac{1 \cdot \sqrt{x + 1} - \color{blue}{\sqrt{x}} \cdot 1}{\frac{\sqrt{x}}{1} \cdot \sqrt{x + 1}} \]
                      9. *-commutativeN/A

                        \[\leadsto \frac{1 \cdot \sqrt{x + 1} - \sqrt{x} \cdot 1}{\color{blue}{\sqrt{x + 1} \cdot \frac{\sqrt{x}}{1}}} \]
                      10. associate-/r*N/A

                        \[\leadsto \color{blue}{\frac{\frac{1 \cdot \sqrt{x + 1} - \sqrt{x} \cdot 1}{\sqrt{x + 1}}}{\frac{\sqrt{x}}{1}}} \]
                      11. lower-/.f64N/A

                        \[\leadsto \color{blue}{\frac{\frac{1 \cdot \sqrt{x + 1} - \sqrt{x} \cdot 1}{\sqrt{x + 1}}}{\frac{\sqrt{x}}{1}}} \]
                    4. Applied rewrites39.2%

                      \[\leadsto \color{blue}{\frac{\frac{\sqrt{x + 1} - \sqrt{x}}{\sqrt{x + 1}}}{\sqrt{x}}} \]
                    5. Taylor expanded in x around inf

                      \[\leadsto \frac{\color{blue}{\frac{\frac{1}{2}}{x}}}{\sqrt{x}} \]
                    6. Step-by-step derivation
                      1. lower-/.f6497.4

                        \[\leadsto \frac{\color{blue}{\frac{0.5}{x}}}{\sqrt{x}} \]
                    7. Applied rewrites97.4%

                      \[\leadsto \frac{\color{blue}{\frac{0.5}{x}}}{\sqrt{x}} \]
                    8. Add Preprocessing

                    Alternative 11: 37.2% accurate, 1.8× speedup?

                    \[\begin{array}{l} \\ \sqrt{\frac{x}{x \cdot x}} \end{array} \]
                    (FPCore (x) :precision binary64 (sqrt (/ x (* x x))))
                    double code(double x) {
                    	return sqrt((x / (x * x)));
                    }
                    
                    real(8) function code(x)
                        real(8), intent (in) :: x
                        code = sqrt((x / (x * x)))
                    end function
                    
                    public static double code(double x) {
                    	return Math.sqrt((x / (x * x)));
                    }
                    
                    def code(x):
                    	return math.sqrt((x / (x * x)))
                    
                    function code(x)
                    	return sqrt(Float64(x / Float64(x * x)))
                    end
                    
                    function tmp = code(x)
                    	tmp = sqrt((x / (x * x)));
                    end
                    
                    code[x_] := N[Sqrt[N[(x / N[(x * x), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]
                    
                    \begin{array}{l}
                    
                    \\
                    \sqrt{\frac{x}{x \cdot x}}
                    \end{array}
                    
                    Derivation
                    1. Initial program 39.1%

                      \[\frac{1}{\sqrt{x}} - \frac{1}{\sqrt{x + 1}} \]
                    2. Add Preprocessing
                    3. Taylor expanded in x around 0

                      \[\leadsto \color{blue}{\sqrt{\frac{1}{x}}} \]
                    4. Step-by-step derivation
                      1. lower-sqrt.f64N/A

                        \[\leadsto \color{blue}{\sqrt{\frac{1}{x}}} \]
                      2. lower-/.f645.8

                        \[\leadsto \sqrt{\color{blue}{\frac{1}{x}}} \]
                    5. Applied rewrites5.8%

                      \[\leadsto \color{blue}{\sqrt{\frac{1}{x}}} \]
                    6. Step-by-step derivation
                      1. Applied rewrites37.4%

                        \[\leadsto \sqrt{\frac{x}{x \cdot x}} \]
                      2. Add Preprocessing

                      Alternative 12: 5.6% accurate, 2.2× speedup?

                      \[\begin{array}{l} \\ \sqrt{\frac{1}{x}} \end{array} \]
                      (FPCore (x) :precision binary64 (sqrt (/ 1.0 x)))
                      double code(double x) {
                      	return sqrt((1.0 / x));
                      }
                      
                      real(8) function code(x)
                          real(8), intent (in) :: x
                          code = sqrt((1.0d0 / x))
                      end function
                      
                      public static double code(double x) {
                      	return Math.sqrt((1.0 / x));
                      }
                      
                      def code(x):
                      	return math.sqrt((1.0 / x))
                      
                      function code(x)
                      	return sqrt(Float64(1.0 / x))
                      end
                      
                      function tmp = code(x)
                      	tmp = sqrt((1.0 / x));
                      end
                      
                      code[x_] := N[Sqrt[N[(1.0 / x), $MachinePrecision]], $MachinePrecision]
                      
                      \begin{array}{l}
                      
                      \\
                      \sqrt{\frac{1}{x}}
                      \end{array}
                      
                      Derivation
                      1. Initial program 39.1%

                        \[\frac{1}{\sqrt{x}} - \frac{1}{\sqrt{x + 1}} \]
                      2. Add Preprocessing
                      3. Taylor expanded in x around 0

                        \[\leadsto \color{blue}{\sqrt{\frac{1}{x}}} \]
                      4. Step-by-step derivation
                        1. lower-sqrt.f64N/A

                          \[\leadsto \color{blue}{\sqrt{\frac{1}{x}}} \]
                        2. lower-/.f645.8

                          \[\leadsto \sqrt{\color{blue}{\frac{1}{x}}} \]
                      5. Applied rewrites5.8%

                        \[\leadsto \color{blue}{\sqrt{\frac{1}{x}}} \]
                      6. Add Preprocessing

                      Developer Target 1: 38.6% accurate, 0.2× speedup?

                      \[\begin{array}{l} \\ {x}^{-0.5} - {\left(x + 1\right)}^{-0.5} \end{array} \]
                      (FPCore (x) :precision binary64 (- (pow x -0.5) (pow (+ x 1.0) -0.5)))
                      double code(double x) {
                      	return pow(x, -0.5) - pow((x + 1.0), -0.5);
                      }
                      
                      real(8) function code(x)
                          real(8), intent (in) :: x
                          code = (x ** (-0.5d0)) - ((x + 1.0d0) ** (-0.5d0))
                      end function
                      
                      public static double code(double x) {
                      	return Math.pow(x, -0.5) - Math.pow((x + 1.0), -0.5);
                      }
                      
                      def code(x):
                      	return math.pow(x, -0.5) - math.pow((x + 1.0), -0.5)
                      
                      function code(x)
                      	return Float64((x ^ -0.5) - (Float64(x + 1.0) ^ -0.5))
                      end
                      
                      function tmp = code(x)
                      	tmp = (x ^ -0.5) - ((x + 1.0) ^ -0.5);
                      end
                      
                      code[x_] := N[(N[Power[x, -0.5], $MachinePrecision] - N[Power[N[(x + 1.0), $MachinePrecision], -0.5], $MachinePrecision]), $MachinePrecision]
                      
                      \begin{array}{l}
                      
                      \\
                      {x}^{-0.5} - {\left(x + 1\right)}^{-0.5}
                      \end{array}
                      

                      Reproduce

                      ?
                      herbie shell --seed 2024312 
                      (FPCore (x)
                        :name "2isqrt (example 3.6)"
                        :precision binary64
                        :pre (and (> x 1.0) (< x 1e+308))
                      
                        :alt
                        (! :herbie-platform default (- (pow x -1/2) (pow (+ x 1) -1/2)))
                      
                        (- (/ 1.0 (sqrt x)) (/ 1.0 (sqrt (+ x 1.0)))))