2tan (problem 3.3.2)

Percentage Accurate: 62.2% → 100.0%
Time: 13.6s
Alternatives: 7
Speedup: 17.3×

Specification

?
\[\left(\left(-10000 \leq x \land x \leq 10000\right) \land 10^{-16} \cdot \left|x\right| < \varepsilon\right) \land \varepsilon < \left|x\right|\]
\[\begin{array}{l} \\ \tan \left(x + \varepsilon\right) - \tan x \end{array} \]
(FPCore (x eps) :precision binary64 (- (tan (+ x eps)) (tan x)))
double code(double x, double eps) {
	return tan((x + eps)) - tan(x);
}
real(8) function code(x, eps)
    real(8), intent (in) :: x
    real(8), intent (in) :: eps
    code = tan((x + eps)) - tan(x)
end function
public static double code(double x, double eps) {
	return Math.tan((x + eps)) - Math.tan(x);
}
def code(x, eps):
	return math.tan((x + eps)) - math.tan(x)
function code(x, eps)
	return Float64(tan(Float64(x + eps)) - tan(x))
end
function tmp = code(x, eps)
	tmp = tan((x + eps)) - tan(x);
end
code[x_, eps_] := N[(N[Tan[N[(x + eps), $MachinePrecision]], $MachinePrecision] - N[Tan[x], $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\tan \left(x + \varepsilon\right) - \tan x
\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 7 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: 62.2% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \tan \left(x + \varepsilon\right) - \tan x \end{array} \]
(FPCore (x eps) :precision binary64 (- (tan (+ x eps)) (tan x)))
double code(double x, double eps) {
	return tan((x + eps)) - tan(x);
}
real(8) function code(x, eps)
    real(8), intent (in) :: x
    real(8), intent (in) :: eps
    code = tan((x + eps)) - tan(x)
end function
public static double code(double x, double eps) {
	return Math.tan((x + eps)) - Math.tan(x);
}
def code(x, eps):
	return math.tan((x + eps)) - math.tan(x)
function code(x, eps)
	return Float64(tan(Float64(x + eps)) - tan(x))
end
function tmp = code(x, eps)
	tmp = tan((x + eps)) - tan(x);
end
code[x_, eps_] := N[(N[Tan[N[(x + eps), $MachinePrecision]], $MachinePrecision] - N[Tan[x], $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\tan \left(x + \varepsilon\right) - \tan x
\end{array}

Alternative 1: 100.0% accurate, 0.3× speedup?

\[\begin{array}{l} \\ \frac{\sin \varepsilon}{\mathsf{fma}\left(\cos x, \cos \varepsilon, \left(-\sin x\right) \cdot \sin \varepsilon\right) \cdot \cos x} \end{array} \]
(FPCore (x eps)
 :precision binary64
 (/ (sin eps) (* (fma (cos x) (cos eps) (* (- (sin x)) (sin eps))) (cos x))))
double code(double x, double eps) {
	return sin(eps) / (fma(cos(x), cos(eps), (-sin(x) * sin(eps))) * cos(x));
}
function code(x, eps)
	return Float64(sin(eps) / Float64(fma(cos(x), cos(eps), Float64(Float64(-sin(x)) * sin(eps))) * cos(x)))
end
code[x_, eps_] := N[(N[Sin[eps], $MachinePrecision] / N[(N[(N[Cos[x], $MachinePrecision] * N[Cos[eps], $MachinePrecision] + N[((-N[Sin[x], $MachinePrecision]) * N[Sin[eps], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] * N[Cos[x], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\frac{\sin \varepsilon}{\mathsf{fma}\left(\cos x, \cos \varepsilon, \left(-\sin x\right) \cdot \sin \varepsilon\right) \cdot \cos x}
\end{array}
Derivation
  1. Initial program 63.9%

    \[\tan \left(x + \varepsilon\right) - \tan x \]
  2. Add Preprocessing
  3. Step-by-step derivation
    1. lift--.f64N/A

      \[\leadsto \color{blue}{\tan \left(x + \varepsilon\right) - \tan x} \]
    2. lift-tan.f64N/A

      \[\leadsto \color{blue}{\tan \left(x + \varepsilon\right)} - \tan x \]
    3. tan-quotN/A

      \[\leadsto \color{blue}{\frac{\sin \left(x + \varepsilon\right)}{\cos \left(x + \varepsilon\right)}} - \tan x \]
    4. lift-tan.f64N/A

      \[\leadsto \frac{\sin \left(x + \varepsilon\right)}{\cos \left(x + \varepsilon\right)} - \color{blue}{\tan x} \]
    5. tan-quotN/A

      \[\leadsto \frac{\sin \left(x + \varepsilon\right)}{\cos \left(x + \varepsilon\right)} - \color{blue}{\frac{\sin x}{\cos x}} \]
    6. frac-subN/A

      \[\leadsto \color{blue}{\frac{\sin \left(x + \varepsilon\right) \cdot \cos x - \cos \left(x + \varepsilon\right) \cdot \sin x}{\cos \left(x + \varepsilon\right) \cdot \cos x}} \]
    7. associate-/r*N/A

      \[\leadsto \color{blue}{\frac{\frac{\sin \left(x + \varepsilon\right) \cdot \cos x - \cos \left(x + \varepsilon\right) \cdot \sin x}{\cos \left(x + \varepsilon\right)}}{\cos x}} \]
    8. lower-/.f64N/A

      \[\leadsto \color{blue}{\frac{\frac{\sin \left(x + \varepsilon\right) \cdot \cos x - \cos \left(x + \varepsilon\right) \cdot \sin x}{\cos \left(x + \varepsilon\right)}}{\cos x}} \]
    9. lower-/.f64N/A

      \[\leadsto \frac{\color{blue}{\frac{\sin \left(x + \varepsilon\right) \cdot \cos x - \cos \left(x + \varepsilon\right) \cdot \sin x}{\cos \left(x + \varepsilon\right)}}}{\cos x} \]
    10. sin-diffN/A

      \[\leadsto \frac{\frac{\color{blue}{\sin \left(\left(x + \varepsilon\right) - x\right)}}{\cos \left(x + \varepsilon\right)}}{\cos x} \]
    11. lower-sin.f64N/A

      \[\leadsto \frac{\frac{\color{blue}{\sin \left(\left(x + \varepsilon\right) - x\right)}}{\cos \left(x + \varepsilon\right)}}{\cos x} \]
    12. lower--.f64N/A

      \[\leadsto \frac{\frac{\sin \color{blue}{\left(\left(x + \varepsilon\right) - x\right)}}{\cos \left(x + \varepsilon\right)}}{\cos x} \]
    13. lift-+.f64N/A

      \[\leadsto \frac{\frac{\sin \left(\color{blue}{\left(x + \varepsilon\right)} - x\right)}{\cos \left(x + \varepsilon\right)}}{\cos x} \]
    14. +-commutativeN/A

      \[\leadsto \frac{\frac{\sin \left(\color{blue}{\left(\varepsilon + x\right)} - x\right)}{\cos \left(x + \varepsilon\right)}}{\cos x} \]
    15. lower-+.f64N/A

      \[\leadsto \frac{\frac{\sin \left(\color{blue}{\left(\varepsilon + x\right)} - x\right)}{\cos \left(x + \varepsilon\right)}}{\cos x} \]
    16. lower-cos.f64N/A

      \[\leadsto \frac{\frac{\sin \left(\left(\varepsilon + x\right) - x\right)}{\color{blue}{\cos \left(x + \varepsilon\right)}}}{\cos x} \]
    17. lift-+.f64N/A

      \[\leadsto \frac{\frac{\sin \left(\left(\varepsilon + x\right) - x\right)}{\cos \color{blue}{\left(x + \varepsilon\right)}}}{\cos x} \]
    18. +-commutativeN/A

      \[\leadsto \frac{\frac{\sin \left(\left(\varepsilon + x\right) - x\right)}{\cos \color{blue}{\left(\varepsilon + x\right)}}}{\cos x} \]
    19. lower-+.f64N/A

      \[\leadsto \frac{\frac{\sin \left(\left(\varepsilon + x\right) - x\right)}{\cos \color{blue}{\left(\varepsilon + x\right)}}}{\cos x} \]
    20. lower-cos.f6464.0

      \[\leadsto \frac{\frac{\sin \left(\left(\varepsilon + x\right) - x\right)}{\cos \left(\varepsilon + x\right)}}{\color{blue}{\cos x}} \]
  4. Applied rewrites64.0%

    \[\leadsto \color{blue}{\frac{\frac{\sin \left(\left(\varepsilon + x\right) - x\right)}{\cos \left(\varepsilon + x\right)}}{\cos x}} \]
  5. Taylor expanded in eps around inf

    \[\leadsto \color{blue}{\frac{\sin \varepsilon}{\cos x \cdot \cos \left(\varepsilon + x\right)}} \]
  6. Step-by-step derivation
    1. lower-/.f64N/A

      \[\leadsto \color{blue}{\frac{\sin \varepsilon}{\cos x \cdot \cos \left(\varepsilon + x\right)}} \]
    2. lower-sin.f64N/A

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

      \[\leadsto \frac{\sin \varepsilon}{\color{blue}{\cos \left(\varepsilon + x\right) \cdot \cos x}} \]
    4. lower-*.f64N/A

      \[\leadsto \frac{\sin \varepsilon}{\color{blue}{\cos \left(\varepsilon + x\right) \cdot \cos x}} \]
    5. lower-cos.f64N/A

      \[\leadsto \frac{\sin \varepsilon}{\color{blue}{\cos \left(\varepsilon + x\right)} \cdot \cos x} \]
    6. +-commutativeN/A

      \[\leadsto \frac{\sin \varepsilon}{\cos \color{blue}{\left(x + \varepsilon\right)} \cdot \cos x} \]
    7. lower-+.f64N/A

      \[\leadsto \frac{\sin \varepsilon}{\cos \color{blue}{\left(x + \varepsilon\right)} \cdot \cos x} \]
    8. lower-cos.f6499.9

      \[\leadsto \frac{\sin \varepsilon}{\cos \left(x + \varepsilon\right) \cdot \color{blue}{\cos x}} \]
  7. Applied rewrites99.9%

    \[\leadsto \color{blue}{\frac{\sin \varepsilon}{\cos \left(x + \varepsilon\right) \cdot \cos x}} \]
  8. Step-by-step derivation
    1. Applied rewrites100.0%

      \[\leadsto \frac{\sin \varepsilon}{\mathsf{fma}\left(\cos x, \cos \varepsilon, \left(-\sin x\right) \cdot \sin \varepsilon\right) \cdot \cos \color{blue}{x}} \]
    2. Add Preprocessing

    Alternative 2: 99.9% accurate, 0.6× speedup?

    \[\begin{array}{l} \\ \frac{\frac{\sin \varepsilon}{\cos \left(x + \varepsilon\right)}}{\cos x} \end{array} \]
    (FPCore (x eps) :precision binary64 (/ (/ (sin eps) (cos (+ x eps))) (cos x)))
    double code(double x, double eps) {
    	return (sin(eps) / cos((x + eps))) / cos(x);
    }
    
    real(8) function code(x, eps)
        real(8), intent (in) :: x
        real(8), intent (in) :: eps
        code = (sin(eps) / cos((x + eps))) / cos(x)
    end function
    
    public static double code(double x, double eps) {
    	return (Math.sin(eps) / Math.cos((x + eps))) / Math.cos(x);
    }
    
    def code(x, eps):
    	return (math.sin(eps) / math.cos((x + eps))) / math.cos(x)
    
    function code(x, eps)
    	return Float64(Float64(sin(eps) / cos(Float64(x + eps))) / cos(x))
    end
    
    function tmp = code(x, eps)
    	tmp = (sin(eps) / cos((x + eps))) / cos(x);
    end
    
    code[x_, eps_] := N[(N[(N[Sin[eps], $MachinePrecision] / N[Cos[N[(x + eps), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] / N[Cos[x], $MachinePrecision]), $MachinePrecision]
    
    \begin{array}{l}
    
    \\
    \frac{\frac{\sin \varepsilon}{\cos \left(x + \varepsilon\right)}}{\cos x}
    \end{array}
    
    Derivation
    1. Initial program 63.9%

      \[\tan \left(x + \varepsilon\right) - \tan x \]
    2. Add Preprocessing
    3. Step-by-step derivation
      1. lift--.f64N/A

        \[\leadsto \color{blue}{\tan \left(x + \varepsilon\right) - \tan x} \]
      2. lift-tan.f64N/A

        \[\leadsto \color{blue}{\tan \left(x + \varepsilon\right)} - \tan x \]
      3. tan-quotN/A

        \[\leadsto \color{blue}{\frac{\sin \left(x + \varepsilon\right)}{\cos \left(x + \varepsilon\right)}} - \tan x \]
      4. lift-tan.f64N/A

        \[\leadsto \frac{\sin \left(x + \varepsilon\right)}{\cos \left(x + \varepsilon\right)} - \color{blue}{\tan x} \]
      5. tan-quotN/A

        \[\leadsto \frac{\sin \left(x + \varepsilon\right)}{\cos \left(x + \varepsilon\right)} - \color{blue}{\frac{\sin x}{\cos x}} \]
      6. frac-subN/A

        \[\leadsto \color{blue}{\frac{\sin \left(x + \varepsilon\right) \cdot \cos x - \cos \left(x + \varepsilon\right) \cdot \sin x}{\cos \left(x + \varepsilon\right) \cdot \cos x}} \]
      7. associate-/r*N/A

        \[\leadsto \color{blue}{\frac{\frac{\sin \left(x + \varepsilon\right) \cdot \cos x - \cos \left(x + \varepsilon\right) \cdot \sin x}{\cos \left(x + \varepsilon\right)}}{\cos x}} \]
      8. lower-/.f64N/A

        \[\leadsto \color{blue}{\frac{\frac{\sin \left(x + \varepsilon\right) \cdot \cos x - \cos \left(x + \varepsilon\right) \cdot \sin x}{\cos \left(x + \varepsilon\right)}}{\cos x}} \]
      9. lower-/.f64N/A

        \[\leadsto \frac{\color{blue}{\frac{\sin \left(x + \varepsilon\right) \cdot \cos x - \cos \left(x + \varepsilon\right) \cdot \sin x}{\cos \left(x + \varepsilon\right)}}}{\cos x} \]
      10. sin-diffN/A

        \[\leadsto \frac{\frac{\color{blue}{\sin \left(\left(x + \varepsilon\right) - x\right)}}{\cos \left(x + \varepsilon\right)}}{\cos x} \]
      11. lower-sin.f64N/A

        \[\leadsto \frac{\frac{\color{blue}{\sin \left(\left(x + \varepsilon\right) - x\right)}}{\cos \left(x + \varepsilon\right)}}{\cos x} \]
      12. lower--.f64N/A

        \[\leadsto \frac{\frac{\sin \color{blue}{\left(\left(x + \varepsilon\right) - x\right)}}{\cos \left(x + \varepsilon\right)}}{\cos x} \]
      13. lift-+.f64N/A

        \[\leadsto \frac{\frac{\sin \left(\color{blue}{\left(x + \varepsilon\right)} - x\right)}{\cos \left(x + \varepsilon\right)}}{\cos x} \]
      14. +-commutativeN/A

        \[\leadsto \frac{\frac{\sin \left(\color{blue}{\left(\varepsilon + x\right)} - x\right)}{\cos \left(x + \varepsilon\right)}}{\cos x} \]
      15. lower-+.f64N/A

        \[\leadsto \frac{\frac{\sin \left(\color{blue}{\left(\varepsilon + x\right)} - x\right)}{\cos \left(x + \varepsilon\right)}}{\cos x} \]
      16. lower-cos.f64N/A

        \[\leadsto \frac{\frac{\sin \left(\left(\varepsilon + x\right) - x\right)}{\color{blue}{\cos \left(x + \varepsilon\right)}}}{\cos x} \]
      17. lift-+.f64N/A

        \[\leadsto \frac{\frac{\sin \left(\left(\varepsilon + x\right) - x\right)}{\cos \color{blue}{\left(x + \varepsilon\right)}}}{\cos x} \]
      18. +-commutativeN/A

        \[\leadsto \frac{\frac{\sin \left(\left(\varepsilon + x\right) - x\right)}{\cos \color{blue}{\left(\varepsilon + x\right)}}}{\cos x} \]
      19. lower-+.f64N/A

        \[\leadsto \frac{\frac{\sin \left(\left(\varepsilon + x\right) - x\right)}{\cos \color{blue}{\left(\varepsilon + x\right)}}}{\cos x} \]
      20. lower-cos.f6464.0

        \[\leadsto \frac{\frac{\sin \left(\left(\varepsilon + x\right) - x\right)}{\cos \left(\varepsilon + x\right)}}{\color{blue}{\cos x}} \]
    4. Applied rewrites64.0%

      \[\leadsto \color{blue}{\frac{\frac{\sin \left(\left(\varepsilon + x\right) - x\right)}{\cos \left(\varepsilon + x\right)}}{\cos x}} \]
    5. Taylor expanded in eps around inf

      \[\leadsto \frac{\frac{\color{blue}{\sin \varepsilon}}{\cos \left(\varepsilon + x\right)}}{\cos x} \]
    6. Step-by-step derivation
      1. lower-sin.f6499.9

        \[\leadsto \frac{\frac{\color{blue}{\sin \varepsilon}}{\cos \left(\varepsilon + x\right)}}{\cos x} \]
    7. Applied rewrites99.9%

      \[\leadsto \frac{\frac{\color{blue}{\sin \varepsilon}}{\cos \left(\varepsilon + x\right)}}{\cos x} \]
    8. Final simplification99.9%

      \[\leadsto \frac{\frac{\sin \varepsilon}{\cos \left(x + \varepsilon\right)}}{\cos x} \]
    9. Add Preprocessing

    Alternative 3: 99.9% accurate, 0.6× speedup?

    \[\begin{array}{l} \\ \frac{\sin \varepsilon}{\cos \left(x + \varepsilon\right) \cdot \cos x} \end{array} \]
    (FPCore (x eps) :precision binary64 (/ (sin eps) (* (cos (+ x eps)) (cos x))))
    double code(double x, double eps) {
    	return sin(eps) / (cos((x + eps)) * cos(x));
    }
    
    real(8) function code(x, eps)
        real(8), intent (in) :: x
        real(8), intent (in) :: eps
        code = sin(eps) / (cos((x + eps)) * cos(x))
    end function
    
    public static double code(double x, double eps) {
    	return Math.sin(eps) / (Math.cos((x + eps)) * Math.cos(x));
    }
    
    def code(x, eps):
    	return math.sin(eps) / (math.cos((x + eps)) * math.cos(x))
    
    function code(x, eps)
    	return Float64(sin(eps) / Float64(cos(Float64(x + eps)) * cos(x)))
    end
    
    function tmp = code(x, eps)
    	tmp = sin(eps) / (cos((x + eps)) * cos(x));
    end
    
    code[x_, eps_] := N[(N[Sin[eps], $MachinePrecision] / N[(N[Cos[N[(x + eps), $MachinePrecision]], $MachinePrecision] * N[Cos[x], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
    
    \begin{array}{l}
    
    \\
    \frac{\sin \varepsilon}{\cos \left(x + \varepsilon\right) \cdot \cos x}
    \end{array}
    
    Derivation
    1. Initial program 63.9%

      \[\tan \left(x + \varepsilon\right) - \tan x \]
    2. Add Preprocessing
    3. Step-by-step derivation
      1. lift--.f64N/A

        \[\leadsto \color{blue}{\tan \left(x + \varepsilon\right) - \tan x} \]
      2. lift-tan.f64N/A

        \[\leadsto \color{blue}{\tan \left(x + \varepsilon\right)} - \tan x \]
      3. tan-quotN/A

        \[\leadsto \color{blue}{\frac{\sin \left(x + \varepsilon\right)}{\cos \left(x + \varepsilon\right)}} - \tan x \]
      4. lift-tan.f64N/A

        \[\leadsto \frac{\sin \left(x + \varepsilon\right)}{\cos \left(x + \varepsilon\right)} - \color{blue}{\tan x} \]
      5. tan-quotN/A

        \[\leadsto \frac{\sin \left(x + \varepsilon\right)}{\cos \left(x + \varepsilon\right)} - \color{blue}{\frac{\sin x}{\cos x}} \]
      6. frac-subN/A

        \[\leadsto \color{blue}{\frac{\sin \left(x + \varepsilon\right) \cdot \cos x - \cos \left(x + \varepsilon\right) \cdot \sin x}{\cos \left(x + \varepsilon\right) \cdot \cos x}} \]
      7. associate-/r*N/A

        \[\leadsto \color{blue}{\frac{\frac{\sin \left(x + \varepsilon\right) \cdot \cos x - \cos \left(x + \varepsilon\right) \cdot \sin x}{\cos \left(x + \varepsilon\right)}}{\cos x}} \]
      8. lower-/.f64N/A

        \[\leadsto \color{blue}{\frac{\frac{\sin \left(x + \varepsilon\right) \cdot \cos x - \cos \left(x + \varepsilon\right) \cdot \sin x}{\cos \left(x + \varepsilon\right)}}{\cos x}} \]
      9. lower-/.f64N/A

        \[\leadsto \frac{\color{blue}{\frac{\sin \left(x + \varepsilon\right) \cdot \cos x - \cos \left(x + \varepsilon\right) \cdot \sin x}{\cos \left(x + \varepsilon\right)}}}{\cos x} \]
      10. sin-diffN/A

        \[\leadsto \frac{\frac{\color{blue}{\sin \left(\left(x + \varepsilon\right) - x\right)}}{\cos \left(x + \varepsilon\right)}}{\cos x} \]
      11. lower-sin.f64N/A

        \[\leadsto \frac{\frac{\color{blue}{\sin \left(\left(x + \varepsilon\right) - x\right)}}{\cos \left(x + \varepsilon\right)}}{\cos x} \]
      12. lower--.f64N/A

        \[\leadsto \frac{\frac{\sin \color{blue}{\left(\left(x + \varepsilon\right) - x\right)}}{\cos \left(x + \varepsilon\right)}}{\cos x} \]
      13. lift-+.f64N/A

        \[\leadsto \frac{\frac{\sin \left(\color{blue}{\left(x + \varepsilon\right)} - x\right)}{\cos \left(x + \varepsilon\right)}}{\cos x} \]
      14. +-commutativeN/A

        \[\leadsto \frac{\frac{\sin \left(\color{blue}{\left(\varepsilon + x\right)} - x\right)}{\cos \left(x + \varepsilon\right)}}{\cos x} \]
      15. lower-+.f64N/A

        \[\leadsto \frac{\frac{\sin \left(\color{blue}{\left(\varepsilon + x\right)} - x\right)}{\cos \left(x + \varepsilon\right)}}{\cos x} \]
      16. lower-cos.f64N/A

        \[\leadsto \frac{\frac{\sin \left(\left(\varepsilon + x\right) - x\right)}{\color{blue}{\cos \left(x + \varepsilon\right)}}}{\cos x} \]
      17. lift-+.f64N/A

        \[\leadsto \frac{\frac{\sin \left(\left(\varepsilon + x\right) - x\right)}{\cos \color{blue}{\left(x + \varepsilon\right)}}}{\cos x} \]
      18. +-commutativeN/A

        \[\leadsto \frac{\frac{\sin \left(\left(\varepsilon + x\right) - x\right)}{\cos \color{blue}{\left(\varepsilon + x\right)}}}{\cos x} \]
      19. lower-+.f64N/A

        \[\leadsto \frac{\frac{\sin \left(\left(\varepsilon + x\right) - x\right)}{\cos \color{blue}{\left(\varepsilon + x\right)}}}{\cos x} \]
      20. lower-cos.f6464.0

        \[\leadsto \frac{\frac{\sin \left(\left(\varepsilon + x\right) - x\right)}{\cos \left(\varepsilon + x\right)}}{\color{blue}{\cos x}} \]
    4. Applied rewrites64.0%

      \[\leadsto \color{blue}{\frac{\frac{\sin \left(\left(\varepsilon + x\right) - x\right)}{\cos \left(\varepsilon + x\right)}}{\cos x}} \]
    5. Taylor expanded in eps around inf

      \[\leadsto \color{blue}{\frac{\sin \varepsilon}{\cos x \cdot \cos \left(\varepsilon + x\right)}} \]
    6. Step-by-step derivation
      1. lower-/.f64N/A

        \[\leadsto \color{blue}{\frac{\sin \varepsilon}{\cos x \cdot \cos \left(\varepsilon + x\right)}} \]
      2. lower-sin.f64N/A

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

        \[\leadsto \frac{\sin \varepsilon}{\color{blue}{\cos \left(\varepsilon + x\right) \cdot \cos x}} \]
      4. lower-*.f64N/A

        \[\leadsto \frac{\sin \varepsilon}{\color{blue}{\cos \left(\varepsilon + x\right) \cdot \cos x}} \]
      5. lower-cos.f64N/A

        \[\leadsto \frac{\sin \varepsilon}{\color{blue}{\cos \left(\varepsilon + x\right)} \cdot \cos x} \]
      6. +-commutativeN/A

        \[\leadsto \frac{\sin \varepsilon}{\cos \color{blue}{\left(x + \varepsilon\right)} \cdot \cos x} \]
      7. lower-+.f64N/A

        \[\leadsto \frac{\sin \varepsilon}{\cos \color{blue}{\left(x + \varepsilon\right)} \cdot \cos x} \]
      8. lower-cos.f6499.9

        \[\leadsto \frac{\sin \varepsilon}{\cos \left(x + \varepsilon\right) \cdot \color{blue}{\cos x}} \]
    7. Applied rewrites99.9%

      \[\leadsto \color{blue}{\frac{\sin \varepsilon}{\cos \left(x + \varepsilon\right) \cdot \cos x}} \]
    8. Add Preprocessing

    Alternative 4: 99.0% accurate, 1.0× speedup?

    \[\begin{array}{l} \\ \mathsf{fma}\left({\tan x}^{2}, \varepsilon, \varepsilon\right) \end{array} \]
    (FPCore (x eps) :precision binary64 (fma (pow (tan x) 2.0) eps eps))
    double code(double x, double eps) {
    	return fma(pow(tan(x), 2.0), eps, eps);
    }
    
    function code(x, eps)
    	return fma((tan(x) ^ 2.0), eps, eps)
    end
    
    code[x_, eps_] := N[(N[Power[N[Tan[x], $MachinePrecision], 2.0], $MachinePrecision] * eps + eps), $MachinePrecision]
    
    \begin{array}{l}
    
    \\
    \mathsf{fma}\left({\tan x}^{2}, \varepsilon, \varepsilon\right)
    \end{array}
    
    Derivation
    1. Initial program 63.9%

      \[\tan \left(x + \varepsilon\right) - \tan x \]
    2. Add Preprocessing
    3. Taylor expanded in eps around 0

      \[\leadsto \color{blue}{\varepsilon \cdot \left(1 - -1 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)} \]
    4. Step-by-step derivation
      1. sub-negN/A

        \[\leadsto \varepsilon \cdot \color{blue}{\left(1 + \left(\mathsf{neg}\left(-1 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)\right)\right)} \]
      2. +-commutativeN/A

        \[\leadsto \varepsilon \cdot \color{blue}{\left(\left(\mathsf{neg}\left(-1 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)\right) + 1\right)} \]
      3. distribute-rgt-inN/A

        \[\leadsto \color{blue}{\left(\mathsf{neg}\left(-1 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)\right) \cdot \varepsilon + 1 \cdot \varepsilon} \]
      4. *-lft-identityN/A

        \[\leadsto \left(\mathsf{neg}\left(-1 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)\right) \cdot \varepsilon + \color{blue}{\varepsilon} \]
      5. lower-fma.f64N/A

        \[\leadsto \color{blue}{\mathsf{fma}\left(\mathsf{neg}\left(-1 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right), \varepsilon, \varepsilon\right)} \]
      6. mul-1-negN/A

        \[\leadsto \mathsf{fma}\left(\mathsf{neg}\left(\color{blue}{\left(\mathsf{neg}\left(\frac{{\sin x}^{2}}{{\cos x}^{2}}\right)\right)}\right), \varepsilon, \varepsilon\right) \]
      7. remove-double-negN/A

        \[\leadsto \mathsf{fma}\left(\color{blue}{\frac{{\sin x}^{2}}{{\cos x}^{2}}}, \varepsilon, \varepsilon\right) \]
      8. lower-/.f64N/A

        \[\leadsto \mathsf{fma}\left(\color{blue}{\frac{{\sin x}^{2}}{{\cos x}^{2}}}, \varepsilon, \varepsilon\right) \]
      9. lower-pow.f64N/A

        \[\leadsto \mathsf{fma}\left(\frac{\color{blue}{{\sin x}^{2}}}{{\cos x}^{2}}, \varepsilon, \varepsilon\right) \]
      10. lower-sin.f64N/A

        \[\leadsto \mathsf{fma}\left(\frac{{\color{blue}{\sin x}}^{2}}{{\cos x}^{2}}, \varepsilon, \varepsilon\right) \]
      11. lower-pow.f64N/A

        \[\leadsto \mathsf{fma}\left(\frac{{\sin x}^{2}}{\color{blue}{{\cos x}^{2}}}, \varepsilon, \varepsilon\right) \]
      12. lower-cos.f6499.2

        \[\leadsto \mathsf{fma}\left(\frac{{\sin x}^{2}}{{\color{blue}{\cos x}}^{2}}, \varepsilon, \varepsilon\right) \]
    5. Applied rewrites99.2%

      \[\leadsto \color{blue}{\mathsf{fma}\left(\frac{{\sin x}^{2}}{{\cos x}^{2}}, \varepsilon, \varepsilon\right)} \]
    6. Step-by-step derivation
      1. Applied rewrites99.2%

        \[\leadsto \color{blue}{\mathsf{fma}\left({\tan x}^{2}, \varepsilon, \varepsilon\right)} \]
      2. Add Preprocessing

      Alternative 5: 98.9% accurate, 1.7× speedup?

      \[\begin{array}{l} \\ \frac{\varepsilon}{1 + \cos \left(-2 \cdot x\right)} \cdot 2 \end{array} \]
      (FPCore (x eps) :precision binary64 (* (/ eps (+ 1.0 (cos (* -2.0 x)))) 2.0))
      double code(double x, double eps) {
      	return (eps / (1.0 + cos((-2.0 * x)))) * 2.0;
      }
      
      real(8) function code(x, eps)
          real(8), intent (in) :: x
          real(8), intent (in) :: eps
          code = (eps / (1.0d0 + cos(((-2.0d0) * x)))) * 2.0d0
      end function
      
      public static double code(double x, double eps) {
      	return (eps / (1.0 + Math.cos((-2.0 * x)))) * 2.0;
      }
      
      def code(x, eps):
      	return (eps / (1.0 + math.cos((-2.0 * x)))) * 2.0
      
      function code(x, eps)
      	return Float64(Float64(eps / Float64(1.0 + cos(Float64(-2.0 * x)))) * 2.0)
      end
      
      function tmp = code(x, eps)
      	tmp = (eps / (1.0 + cos((-2.0 * x)))) * 2.0;
      end
      
      code[x_, eps_] := N[(N[(eps / N[(1.0 + N[Cos[N[(-2.0 * x), $MachinePrecision]], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] * 2.0), $MachinePrecision]
      
      \begin{array}{l}
      
      \\
      \frac{\varepsilon}{1 + \cos \left(-2 \cdot x\right)} \cdot 2
      \end{array}
      
      Derivation
      1. Initial program 63.9%

        \[\tan \left(x + \varepsilon\right) - \tan x \]
      2. Add Preprocessing
      3. Step-by-step derivation
        1. lift--.f64N/A

          \[\leadsto \color{blue}{\tan \left(x + \varepsilon\right) - \tan x} \]
        2. lift-tan.f64N/A

          \[\leadsto \color{blue}{\tan \left(x + \varepsilon\right)} - \tan x \]
        3. tan-quotN/A

          \[\leadsto \color{blue}{\frac{\sin \left(x + \varepsilon\right)}{\cos \left(x + \varepsilon\right)}} - \tan x \]
        4. lift-tan.f64N/A

          \[\leadsto \frac{\sin \left(x + \varepsilon\right)}{\cos \left(x + \varepsilon\right)} - \color{blue}{\tan x} \]
        5. tan-quotN/A

          \[\leadsto \frac{\sin \left(x + \varepsilon\right)}{\cos \left(x + \varepsilon\right)} - \color{blue}{\frac{\sin x}{\cos x}} \]
        6. frac-subN/A

          \[\leadsto \color{blue}{\frac{\sin \left(x + \varepsilon\right) \cdot \cos x - \cos \left(x + \varepsilon\right) \cdot \sin x}{\cos \left(x + \varepsilon\right) \cdot \cos x}} \]
        7. associate-/r*N/A

          \[\leadsto \color{blue}{\frac{\frac{\sin \left(x + \varepsilon\right) \cdot \cos x - \cos \left(x + \varepsilon\right) \cdot \sin x}{\cos \left(x + \varepsilon\right)}}{\cos x}} \]
        8. lower-/.f64N/A

          \[\leadsto \color{blue}{\frac{\frac{\sin \left(x + \varepsilon\right) \cdot \cos x - \cos \left(x + \varepsilon\right) \cdot \sin x}{\cos \left(x + \varepsilon\right)}}{\cos x}} \]
        9. lower-/.f64N/A

          \[\leadsto \frac{\color{blue}{\frac{\sin \left(x + \varepsilon\right) \cdot \cos x - \cos \left(x + \varepsilon\right) \cdot \sin x}{\cos \left(x + \varepsilon\right)}}}{\cos x} \]
        10. sin-diffN/A

          \[\leadsto \frac{\frac{\color{blue}{\sin \left(\left(x + \varepsilon\right) - x\right)}}{\cos \left(x + \varepsilon\right)}}{\cos x} \]
        11. lower-sin.f64N/A

          \[\leadsto \frac{\frac{\color{blue}{\sin \left(\left(x + \varepsilon\right) - x\right)}}{\cos \left(x + \varepsilon\right)}}{\cos x} \]
        12. lower--.f64N/A

          \[\leadsto \frac{\frac{\sin \color{blue}{\left(\left(x + \varepsilon\right) - x\right)}}{\cos \left(x + \varepsilon\right)}}{\cos x} \]
        13. lift-+.f64N/A

          \[\leadsto \frac{\frac{\sin \left(\color{blue}{\left(x + \varepsilon\right)} - x\right)}{\cos \left(x + \varepsilon\right)}}{\cos x} \]
        14. +-commutativeN/A

          \[\leadsto \frac{\frac{\sin \left(\color{blue}{\left(\varepsilon + x\right)} - x\right)}{\cos \left(x + \varepsilon\right)}}{\cos x} \]
        15. lower-+.f64N/A

          \[\leadsto \frac{\frac{\sin \left(\color{blue}{\left(\varepsilon + x\right)} - x\right)}{\cos \left(x + \varepsilon\right)}}{\cos x} \]
        16. lower-cos.f64N/A

          \[\leadsto \frac{\frac{\sin \left(\left(\varepsilon + x\right) - x\right)}{\color{blue}{\cos \left(x + \varepsilon\right)}}}{\cos x} \]
        17. lift-+.f64N/A

          \[\leadsto \frac{\frac{\sin \left(\left(\varepsilon + x\right) - x\right)}{\cos \color{blue}{\left(x + \varepsilon\right)}}}{\cos x} \]
        18. +-commutativeN/A

          \[\leadsto \frac{\frac{\sin \left(\left(\varepsilon + x\right) - x\right)}{\cos \color{blue}{\left(\varepsilon + x\right)}}}{\cos x} \]
        19. lower-+.f64N/A

          \[\leadsto \frac{\frac{\sin \left(\left(\varepsilon + x\right) - x\right)}{\cos \color{blue}{\left(\varepsilon + x\right)}}}{\cos x} \]
        20. lower-cos.f6464.0

          \[\leadsto \frac{\frac{\sin \left(\left(\varepsilon + x\right) - x\right)}{\cos \left(\varepsilon + x\right)}}{\color{blue}{\cos x}} \]
      4. Applied rewrites64.0%

        \[\leadsto \color{blue}{\frac{\frac{\sin \left(\left(\varepsilon + x\right) - x\right)}{\cos \left(\varepsilon + x\right)}}{\cos x}} \]
      5. Taylor expanded in eps around inf

        \[\leadsto \frac{\frac{\color{blue}{\sin \varepsilon}}{\cos \left(\varepsilon + x\right)}}{\cos x} \]
      6. Step-by-step derivation
        1. lower-sin.f6499.9

          \[\leadsto \frac{\frac{\color{blue}{\sin \varepsilon}}{\cos \left(\varepsilon + x\right)}}{\cos x} \]
      7. Applied rewrites99.9%

        \[\leadsto \frac{\frac{\color{blue}{\sin \varepsilon}}{\cos \left(\varepsilon + x\right)}}{\cos x} \]
      8. Step-by-step derivation
        1. lift-/.f64N/A

          \[\leadsto \color{blue}{\frac{\frac{\sin \varepsilon}{\cos \left(\varepsilon + x\right)}}{\cos x}} \]
        2. lift-/.f64N/A

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

          \[\leadsto \color{blue}{\frac{\sin \varepsilon}{\cos \left(\varepsilon + x\right) \cdot \cos x}} \]
        4. lift-+.f64N/A

          \[\leadsto \frac{\sin \varepsilon}{\cos \color{blue}{\left(\varepsilon + x\right)} \cdot \cos x} \]
        5. lift-cos.f64N/A

          \[\leadsto \frac{\sin \varepsilon}{\color{blue}{\cos \left(\varepsilon + x\right)} \cdot \cos x} \]
        6. +-commutativeN/A

          \[\leadsto \frac{\sin \varepsilon}{\cos \color{blue}{\left(x + \varepsilon\right)} \cdot \cos x} \]
        7. lift-+.f64N/A

          \[\leadsto \frac{\sin \varepsilon}{\cos \color{blue}{\left(x + \varepsilon\right)} \cdot \cos x} \]
        8. lift-cos.f64N/A

          \[\leadsto \frac{\sin \varepsilon}{\cos \left(x + \varepsilon\right) \cdot \color{blue}{\cos x}} \]
        9. cos-multN/A

          \[\leadsto \frac{\sin \varepsilon}{\color{blue}{\frac{\cos \left(\left(x + \varepsilon\right) + x\right) + \cos \left(\left(x + \varepsilon\right) - x\right)}{2}}} \]
        10. associate-/r/N/A

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

          \[\leadsto \color{blue}{\frac{\sin \varepsilon}{\cos \left(\left(x + \varepsilon\right) + x\right) + \cos \left(\left(x + \varepsilon\right) - x\right)} \cdot 2} \]
      9. Applied rewrites99.9%

        \[\leadsto \color{blue}{\frac{\sin \varepsilon}{\cos \left(0 + \varepsilon\right) + \cos \left(\left(x + \varepsilon\right) + x\right)} \cdot 2} \]
      10. Taylor expanded in eps around 0

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

          \[\leadsto \color{blue}{\frac{\varepsilon}{1 + \cos \left(2 \cdot x\right)}} \cdot 2 \]
        2. +-commutativeN/A

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

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

          \[\leadsto \frac{\varepsilon}{\cos \left(\color{blue}{\left(\mathsf{neg}\left(-2\right)\right)} \cdot x\right) + 1} \cdot 2 \]
        5. distribute-lft-neg-inN/A

          \[\leadsto \frac{\varepsilon}{\cos \color{blue}{\left(\mathsf{neg}\left(-2 \cdot x\right)\right)} + 1} \cdot 2 \]
        6. cos-negN/A

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

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

          \[\leadsto \frac{\varepsilon}{\cos \color{blue}{\left(-2 \cdot x\right)} + 1} \cdot 2 \]
      12. Applied rewrites99.1%

        \[\leadsto \color{blue}{\frac{\varepsilon}{\cos \left(-2 \cdot x\right) + 1}} \cdot 2 \]
      13. Final simplification99.1%

        \[\leadsto \frac{\varepsilon}{1 + \cos \left(-2 \cdot x\right)} \cdot 2 \]
      14. Add Preprocessing

      Alternative 6: 98.3% accurate, 7.4× speedup?

      \[\begin{array}{l} \\ \mathsf{fma}\left(\left(\mathsf{fma}\left(x \cdot x, 0.6666666666666666, 1\right) \cdot x\right) \cdot x, \varepsilon, \varepsilon\right) \end{array} \]
      (FPCore (x eps)
       :precision binary64
       (fma (* (* (fma (* x x) 0.6666666666666666 1.0) x) x) eps eps))
      double code(double x, double eps) {
      	return fma(((fma((x * x), 0.6666666666666666, 1.0) * x) * x), eps, eps);
      }
      
      function code(x, eps)
      	return fma(Float64(Float64(fma(Float64(x * x), 0.6666666666666666, 1.0) * x) * x), eps, eps)
      end
      
      code[x_, eps_] := N[(N[(N[(N[(N[(x * x), $MachinePrecision] * 0.6666666666666666 + 1.0), $MachinePrecision] * x), $MachinePrecision] * x), $MachinePrecision] * eps + eps), $MachinePrecision]
      
      \begin{array}{l}
      
      \\
      \mathsf{fma}\left(\left(\mathsf{fma}\left(x \cdot x, 0.6666666666666666, 1\right) \cdot x\right) \cdot x, \varepsilon, \varepsilon\right)
      \end{array}
      
      Derivation
      1. Initial program 63.9%

        \[\tan \left(x + \varepsilon\right) - \tan x \]
      2. Add Preprocessing
      3. Taylor expanded in eps around 0

        \[\leadsto \color{blue}{\varepsilon \cdot \left(1 - -1 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)} \]
      4. Step-by-step derivation
        1. sub-negN/A

          \[\leadsto \varepsilon \cdot \color{blue}{\left(1 + \left(\mathsf{neg}\left(-1 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)\right)\right)} \]
        2. +-commutativeN/A

          \[\leadsto \varepsilon \cdot \color{blue}{\left(\left(\mathsf{neg}\left(-1 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)\right) + 1\right)} \]
        3. distribute-rgt-inN/A

          \[\leadsto \color{blue}{\left(\mathsf{neg}\left(-1 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)\right) \cdot \varepsilon + 1 \cdot \varepsilon} \]
        4. *-lft-identityN/A

          \[\leadsto \left(\mathsf{neg}\left(-1 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)\right) \cdot \varepsilon + \color{blue}{\varepsilon} \]
        5. lower-fma.f64N/A

          \[\leadsto \color{blue}{\mathsf{fma}\left(\mathsf{neg}\left(-1 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right), \varepsilon, \varepsilon\right)} \]
        6. mul-1-negN/A

          \[\leadsto \mathsf{fma}\left(\mathsf{neg}\left(\color{blue}{\left(\mathsf{neg}\left(\frac{{\sin x}^{2}}{{\cos x}^{2}}\right)\right)}\right), \varepsilon, \varepsilon\right) \]
        7. remove-double-negN/A

          \[\leadsto \mathsf{fma}\left(\color{blue}{\frac{{\sin x}^{2}}{{\cos x}^{2}}}, \varepsilon, \varepsilon\right) \]
        8. lower-/.f64N/A

          \[\leadsto \mathsf{fma}\left(\color{blue}{\frac{{\sin x}^{2}}{{\cos x}^{2}}}, \varepsilon, \varepsilon\right) \]
        9. lower-pow.f64N/A

          \[\leadsto \mathsf{fma}\left(\frac{\color{blue}{{\sin x}^{2}}}{{\cos x}^{2}}, \varepsilon, \varepsilon\right) \]
        10. lower-sin.f64N/A

          \[\leadsto \mathsf{fma}\left(\frac{{\color{blue}{\sin x}}^{2}}{{\cos x}^{2}}, \varepsilon, \varepsilon\right) \]
        11. lower-pow.f64N/A

          \[\leadsto \mathsf{fma}\left(\frac{{\sin x}^{2}}{\color{blue}{{\cos x}^{2}}}, \varepsilon, \varepsilon\right) \]
        12. lower-cos.f6499.2

          \[\leadsto \mathsf{fma}\left(\frac{{\sin x}^{2}}{{\color{blue}{\cos x}}^{2}}, \varepsilon, \varepsilon\right) \]
      5. Applied rewrites99.2%

        \[\leadsto \color{blue}{\mathsf{fma}\left(\frac{{\sin x}^{2}}{{\cos x}^{2}}, \varepsilon, \varepsilon\right)} \]
      6. Taylor expanded in x around 0

        \[\leadsto \mathsf{fma}\left({x}^{2} \cdot \left(1 + \frac{2}{3} \cdot {x}^{2}\right), \varepsilon, \varepsilon\right) \]
      7. Step-by-step derivation
        1. Applied rewrites98.9%

          \[\leadsto \mathsf{fma}\left(\left(\mathsf{fma}\left(x \cdot x, 0.6666666666666666, 1\right) \cdot x\right) \cdot x, \varepsilon, \varepsilon\right) \]
        2. Add Preprocessing

        Alternative 7: 98.3% accurate, 17.3× speedup?

        \[\begin{array}{l} \\ \mathsf{fma}\left(x \cdot x, \varepsilon, \varepsilon\right) \end{array} \]
        (FPCore (x eps) :precision binary64 (fma (* x x) eps eps))
        double code(double x, double eps) {
        	return fma((x * x), eps, eps);
        }
        
        function code(x, eps)
        	return fma(Float64(x * x), eps, eps)
        end
        
        code[x_, eps_] := N[(N[(x * x), $MachinePrecision] * eps + eps), $MachinePrecision]
        
        \begin{array}{l}
        
        \\
        \mathsf{fma}\left(x \cdot x, \varepsilon, \varepsilon\right)
        \end{array}
        
        Derivation
        1. Initial program 63.9%

          \[\tan \left(x + \varepsilon\right) - \tan x \]
        2. Add Preprocessing
        3. Taylor expanded in eps around 0

          \[\leadsto \color{blue}{\varepsilon \cdot \left(1 - -1 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)} \]
        4. Step-by-step derivation
          1. sub-negN/A

            \[\leadsto \varepsilon \cdot \color{blue}{\left(1 + \left(\mathsf{neg}\left(-1 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)\right)\right)} \]
          2. +-commutativeN/A

            \[\leadsto \varepsilon \cdot \color{blue}{\left(\left(\mathsf{neg}\left(-1 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)\right) + 1\right)} \]
          3. distribute-rgt-inN/A

            \[\leadsto \color{blue}{\left(\mathsf{neg}\left(-1 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)\right) \cdot \varepsilon + 1 \cdot \varepsilon} \]
          4. *-lft-identityN/A

            \[\leadsto \left(\mathsf{neg}\left(-1 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right)\right) \cdot \varepsilon + \color{blue}{\varepsilon} \]
          5. lower-fma.f64N/A

            \[\leadsto \color{blue}{\mathsf{fma}\left(\mathsf{neg}\left(-1 \cdot \frac{{\sin x}^{2}}{{\cos x}^{2}}\right), \varepsilon, \varepsilon\right)} \]
          6. mul-1-negN/A

            \[\leadsto \mathsf{fma}\left(\mathsf{neg}\left(\color{blue}{\left(\mathsf{neg}\left(\frac{{\sin x}^{2}}{{\cos x}^{2}}\right)\right)}\right), \varepsilon, \varepsilon\right) \]
          7. remove-double-negN/A

            \[\leadsto \mathsf{fma}\left(\color{blue}{\frac{{\sin x}^{2}}{{\cos x}^{2}}}, \varepsilon, \varepsilon\right) \]
          8. lower-/.f64N/A

            \[\leadsto \mathsf{fma}\left(\color{blue}{\frac{{\sin x}^{2}}{{\cos x}^{2}}}, \varepsilon, \varepsilon\right) \]
          9. lower-pow.f64N/A

            \[\leadsto \mathsf{fma}\left(\frac{\color{blue}{{\sin x}^{2}}}{{\cos x}^{2}}, \varepsilon, \varepsilon\right) \]
          10. lower-sin.f64N/A

            \[\leadsto \mathsf{fma}\left(\frac{{\color{blue}{\sin x}}^{2}}{{\cos x}^{2}}, \varepsilon, \varepsilon\right) \]
          11. lower-pow.f64N/A

            \[\leadsto \mathsf{fma}\left(\frac{{\sin x}^{2}}{\color{blue}{{\cos x}^{2}}}, \varepsilon, \varepsilon\right) \]
          12. lower-cos.f6499.2

            \[\leadsto \mathsf{fma}\left(\frac{{\sin x}^{2}}{{\color{blue}{\cos x}}^{2}}, \varepsilon, \varepsilon\right) \]
        5. Applied rewrites99.2%

          \[\leadsto \color{blue}{\mathsf{fma}\left(\frac{{\sin x}^{2}}{{\cos x}^{2}}, \varepsilon, \varepsilon\right)} \]
        6. Taylor expanded in x around 0

          \[\leadsto \mathsf{fma}\left({x}^{2}, \varepsilon, \varepsilon\right) \]
        7. Step-by-step derivation
          1. Applied rewrites98.9%

            \[\leadsto \mathsf{fma}\left(x \cdot x, \varepsilon, \varepsilon\right) \]
          2. Add Preprocessing

          Developer Target 1: 99.0% accurate, 1.0× speedup?

          \[\begin{array}{l} \\ \varepsilon + \left(\varepsilon \cdot \tan x\right) \cdot \tan x \end{array} \]
          (FPCore (x eps) :precision binary64 (+ eps (* (* eps (tan x)) (tan x))))
          double code(double x, double eps) {
          	return eps + ((eps * tan(x)) * tan(x));
          }
          
          real(8) function code(x, eps)
              real(8), intent (in) :: x
              real(8), intent (in) :: eps
              code = eps + ((eps * tan(x)) * tan(x))
          end function
          
          public static double code(double x, double eps) {
          	return eps + ((eps * Math.tan(x)) * Math.tan(x));
          }
          
          def code(x, eps):
          	return eps + ((eps * math.tan(x)) * math.tan(x))
          
          function code(x, eps)
          	return Float64(eps + Float64(Float64(eps * tan(x)) * tan(x)))
          end
          
          function tmp = code(x, eps)
          	tmp = eps + ((eps * tan(x)) * tan(x));
          end
          
          code[x_, eps_] := N[(eps + N[(N[(eps * N[Tan[x], $MachinePrecision]), $MachinePrecision] * N[Tan[x], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
          
          \begin{array}{l}
          
          \\
          \varepsilon + \left(\varepsilon \cdot \tan x\right) \cdot \tan x
          \end{array}
          

          Reproduce

          ?
          herbie shell --seed 2024266 
          (FPCore (x eps)
            :name "2tan (problem 3.3.2)"
            :precision binary64
            :pre (and (and (and (<= -10000.0 x) (<= x 10000.0)) (< (* 1e-16 (fabs x)) eps)) (< eps (fabs x)))
          
            :alt
            (! :herbie-platform default (+ eps (* eps (tan x) (tan x))))
          
            (- (tan (+ x eps)) (tan x)))