Quadratic roots, medium range

Percentage Accurate: 31.7% → 95.3%
Time: 11.4s
Alternatives: 7
Speedup: 3.6×

Specification

?
\[\left(\left(1.1102230246251565 \cdot 10^{-16} < a \land a < 9007199254740992\right) \land \left(1.1102230246251565 \cdot 10^{-16} < b \land b < 9007199254740992\right)\right) \land \left(1.1102230246251565 \cdot 10^{-16} < c \land c < 9007199254740992\right)\]
\[\begin{array}{l} \\ \frac{\left(-b\right) + \sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c}}{2 \cdot a} \end{array} \]
(FPCore (a b c)
 :precision binary64
 (/ (+ (- b) (sqrt (- (* b b) (* (* 4.0 a) c)))) (* 2.0 a)))
double code(double a, double b, double c) {
	return (-b + sqrt(((b * b) - ((4.0 * a) * c)))) / (2.0 * a);
}
real(8) function code(a, b, c)
    real(8), intent (in) :: a
    real(8), intent (in) :: b
    real(8), intent (in) :: c
    code = (-b + sqrt(((b * b) - ((4.0d0 * a) * c)))) / (2.0d0 * a)
end function
public static double code(double a, double b, double c) {
	return (-b + Math.sqrt(((b * b) - ((4.0 * a) * c)))) / (2.0 * a);
}
def code(a, b, c):
	return (-b + math.sqrt(((b * b) - ((4.0 * a) * c)))) / (2.0 * a)
function code(a, b, c)
	return Float64(Float64(Float64(-b) + sqrt(Float64(Float64(b * b) - Float64(Float64(4.0 * a) * c)))) / Float64(2.0 * a))
end
function tmp = code(a, b, c)
	tmp = (-b + sqrt(((b * b) - ((4.0 * a) * c)))) / (2.0 * a);
end
code[a_, b_, c_] := N[(N[((-b) + N[Sqrt[N[(N[(b * b), $MachinePrecision] - N[(N[(4.0 * a), $MachinePrecision] * c), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] / N[(2.0 * a), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\frac{\left(-b\right) + \sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c}}{2 \cdot a}
\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: 31.7% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \frac{\left(-b\right) + \sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c}}{2 \cdot a} \end{array} \]
(FPCore (a b c)
 :precision binary64
 (/ (+ (- b) (sqrt (- (* b b) (* (* 4.0 a) c)))) (* 2.0 a)))
double code(double a, double b, double c) {
	return (-b + sqrt(((b * b) - ((4.0 * a) * c)))) / (2.0 * a);
}
real(8) function code(a, b, c)
    real(8), intent (in) :: a
    real(8), intent (in) :: b
    real(8), intent (in) :: c
    code = (-b + sqrt(((b * b) - ((4.0d0 * a) * c)))) / (2.0d0 * a)
end function
public static double code(double a, double b, double c) {
	return (-b + Math.sqrt(((b * b) - ((4.0 * a) * c)))) / (2.0 * a);
}
def code(a, b, c):
	return (-b + math.sqrt(((b * b) - ((4.0 * a) * c)))) / (2.0 * a)
function code(a, b, c)
	return Float64(Float64(Float64(-b) + sqrt(Float64(Float64(b * b) - Float64(Float64(4.0 * a) * c)))) / Float64(2.0 * a))
end
function tmp = code(a, b, c)
	tmp = (-b + sqrt(((b * b) - ((4.0 * a) * c)))) / (2.0 * a);
end
code[a_, b_, c_] := N[(N[((-b) + N[Sqrt[N[(N[(b * b), $MachinePrecision] - N[(N[(4.0 * a), $MachinePrecision] * c), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] / N[(2.0 * a), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\frac{\left(-b\right) + \sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c}}{2 \cdot a}
\end{array}

Alternative 1: 95.3% accurate, 0.2× speedup?

\[\begin{array}{l} \\ \frac{0.5}{\frac{\mathsf{fma}\left(\mathsf{fma}\left(\mathsf{fma}\left(-c, \frac{-{a}^{3}}{{b}^{5}}, \frac{\frac{\left(-0.5 \cdot a\right) \cdot a}{b \cdot b}}{-b}\right), c, \frac{a}{b} \cdot 0.5\right), c, -0.5 \cdot b\right)}{c}} \end{array} \]
(FPCore (a b c)
 :precision binary64
 (/
  0.5
  (/
   (fma
    (fma
     (fma
      (- c)
      (/ (- (pow a 3.0)) (pow b 5.0))
      (/ (/ (* (* -0.5 a) a) (* b b)) (- b)))
     c
     (* (/ a b) 0.5))
    c
    (* -0.5 b))
   c)))
double code(double a, double b, double c) {
	return 0.5 / (fma(fma(fma(-c, (-pow(a, 3.0) / pow(b, 5.0)), ((((-0.5 * a) * a) / (b * b)) / -b)), c, ((a / b) * 0.5)), c, (-0.5 * b)) / c);
}
function code(a, b, c)
	return Float64(0.5 / Float64(fma(fma(fma(Float64(-c), Float64(Float64(-(a ^ 3.0)) / (b ^ 5.0)), Float64(Float64(Float64(Float64(-0.5 * a) * a) / Float64(b * b)) / Float64(-b))), c, Float64(Float64(a / b) * 0.5)), c, Float64(-0.5 * b)) / c))
end
code[a_, b_, c_] := N[(0.5 / N[(N[(N[(N[((-c) * N[((-N[Power[a, 3.0], $MachinePrecision]) / N[Power[b, 5.0], $MachinePrecision]), $MachinePrecision] + N[(N[(N[(N[(-0.5 * a), $MachinePrecision] * a), $MachinePrecision] / N[(b * b), $MachinePrecision]), $MachinePrecision] / (-b)), $MachinePrecision]), $MachinePrecision] * c + N[(N[(a / b), $MachinePrecision] * 0.5), $MachinePrecision]), $MachinePrecision] * c + N[(-0.5 * b), $MachinePrecision]), $MachinePrecision] / c), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\frac{0.5}{\frac{\mathsf{fma}\left(\mathsf{fma}\left(\mathsf{fma}\left(-c, \frac{-{a}^{3}}{{b}^{5}}, \frac{\frac{\left(-0.5 \cdot a\right) \cdot a}{b \cdot b}}{-b}\right), c, \frac{a}{b} \cdot 0.5\right), c, -0.5 \cdot b\right)}{c}}
\end{array}
Derivation
  1. Initial program 29.0%

    \[\frac{\left(-b\right) + \sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c}}{2 \cdot a} \]
  2. Add Preprocessing
  3. Step-by-step derivation
    1. lift-/.f64N/A

      \[\leadsto \color{blue}{\frac{\left(-b\right) + \sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c}}{2 \cdot a}} \]
    2. clear-numN/A

      \[\leadsto \color{blue}{\frac{1}{\frac{2 \cdot a}{\left(-b\right) + \sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c}}}} \]
    3. lift-*.f64N/A

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

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

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

      \[\leadsto \frac{\color{blue}{\frac{1}{2}}}{\frac{a}{\left(-b\right) + \sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c}}} \]
    7. lower-/.f64N/A

      \[\leadsto \color{blue}{\frac{\frac{1}{2}}{\frac{a}{\left(-b\right) + \sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c}}}} \]
    8. lower-/.f6429.0

      \[\leadsto \frac{0.5}{\color{blue}{\frac{a}{\left(-b\right) + \sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c}}}} \]
    9. lift-+.f64N/A

      \[\leadsto \frac{\frac{1}{2}}{\frac{a}{\color{blue}{\left(-b\right) + \sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c}}}} \]
    10. +-commutativeN/A

      \[\leadsto \frac{\frac{1}{2}}{\frac{a}{\color{blue}{\sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c} + \left(-b\right)}}} \]
    11. lift-neg.f64N/A

      \[\leadsto \frac{\frac{1}{2}}{\frac{a}{\sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c} + \color{blue}{\left(\mathsf{neg}\left(b\right)\right)}}} \]
    12. unsub-negN/A

      \[\leadsto \frac{\frac{1}{2}}{\frac{a}{\color{blue}{\sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c} - b}}} \]
    13. lower--.f6429.0

      \[\leadsto \frac{0.5}{\frac{a}{\color{blue}{\sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c} - b}}} \]
  4. Applied rewrites29.0%

    \[\leadsto \color{blue}{\frac{0.5}{\frac{a}{\sqrt{\mathsf{fma}\left(-4 \cdot c, a, b \cdot b\right)} - b}}} \]
  5. Taylor expanded in c around 0

    \[\leadsto \frac{\frac{1}{2}}{\color{blue}{\frac{\frac{-1}{2} \cdot b + c \cdot \left(c \cdot \left(-1 \cdot \left(c \cdot \left(-1 \cdot \frac{a \cdot \left(-1 \cdot \frac{{a}^{2}}{{b}^{3}} + \frac{1}{2} \cdot \frac{{a}^{2}}{{b}^{3}}\right)}{{b}^{2}} + \left(\frac{-1}{8} \cdot \frac{b \cdot \left(4 \cdot \frac{{a}^{4}}{{b}^{6}} + 16 \cdot \frac{{a}^{4}}{{b}^{6}}\right)}{a} + \frac{{a}^{3}}{{b}^{5}}\right)\right)\right) - \left(-1 \cdot \frac{{a}^{2}}{{b}^{3}} + \frac{1}{2} \cdot \frac{{a}^{2}}{{b}^{3}}\right)\right) - \frac{-1}{2} \cdot \frac{a}{b}\right)}{c}}} \]
  6. Applied rewrites96.4%

    \[\leadsto \frac{0.5}{\color{blue}{\frac{\mathsf{fma}\left(\mathsf{fma}\left(\mathsf{fma}\left(-c, \mathsf{fma}\left(b \cdot \frac{\frac{{a}^{4}}{{b}^{6}} \cdot 20}{a}, -0.125, \frac{{a}^{3}}{{b}^{5}}\right) - \frac{\frac{a \cdot a}{{b}^{3}} \cdot -0.5}{b} \cdot \frac{a}{b}, \frac{-a \cdot a}{{b}^{3}} \cdot -0.5\right), c, \frac{a}{b} \cdot 0.5\right), c, -0.5 \cdot b\right)}{c}}} \]
  7. Taylor expanded in a around 0

    \[\leadsto \frac{\frac{1}{2}}{\frac{\mathsf{fma}\left(\mathsf{fma}\left(\mathsf{fma}\left(-c, -1 \cdot \frac{{a}^{3}}{{b}^{5}}, \frac{-a \cdot a}{{b}^{3}} \cdot \frac{-1}{2}\right), c, \frac{a}{b} \cdot \frac{1}{2}\right), c, \frac{-1}{2} \cdot b\right)}{c}} \]
  8. Step-by-step derivation
    1. Applied rewrites96.4%

      \[\leadsto \frac{0.5}{\frac{\mathsf{fma}\left(\mathsf{fma}\left(\mathsf{fma}\left(-c, \frac{-{a}^{3}}{{b}^{5}}, \frac{-a \cdot a}{{b}^{3}} \cdot -0.5\right), c, \frac{a}{b} \cdot 0.5\right), c, -0.5 \cdot b\right)}{c}} \]
    2. Step-by-step derivation
      1. Applied rewrites96.4%

        \[\leadsto \frac{0.5}{\frac{\mathsf{fma}\left(\mathsf{fma}\left(\mathsf{fma}\left(-c, \frac{-{a}^{3}}{{b}^{5}}, \frac{\frac{\left(-a\right) \cdot \left(a \cdot -0.5\right)}{b \cdot b}}{b}\right), c, \frac{a}{b} \cdot 0.5\right), c, -0.5 \cdot b\right)}{c}} \]
      2. Final simplification96.4%

        \[\leadsto \frac{0.5}{\frac{\mathsf{fma}\left(\mathsf{fma}\left(\mathsf{fma}\left(-c, \frac{-{a}^{3}}{{b}^{5}}, \frac{\frac{\left(-0.5 \cdot a\right) \cdot a}{b \cdot b}}{-b}\right), c, \frac{a}{b} \cdot 0.5\right), c, -0.5 \cdot b\right)}{c}} \]
      3. Add Preprocessing

      Alternative 2: 95.3% accurate, 0.2× speedup?

      \[\begin{array}{l} \\ \frac{0.5}{\mathsf{fma}\left(a, \mathsf{fma}\left(a, \mathsf{fma}\left(0.5, \frac{c}{{b}^{3}}, \frac{\left(c \cdot c\right) \cdot a}{{b}^{5}}\right), \frac{0.5}{b}\right), \frac{b}{c} \cdot -0.5\right)} \end{array} \]
      (FPCore (a b c)
       :precision binary64
       (/
        0.5
        (fma
         a
         (fma a (fma 0.5 (/ c (pow b 3.0)) (/ (* (* c c) a) (pow b 5.0))) (/ 0.5 b))
         (* (/ b c) -0.5))))
      double code(double a, double b, double c) {
      	return 0.5 / fma(a, fma(a, fma(0.5, (c / pow(b, 3.0)), (((c * c) * a) / pow(b, 5.0))), (0.5 / b)), ((b / c) * -0.5));
      }
      
      function code(a, b, c)
      	return Float64(0.5 / fma(a, fma(a, fma(0.5, Float64(c / (b ^ 3.0)), Float64(Float64(Float64(c * c) * a) / (b ^ 5.0))), Float64(0.5 / b)), Float64(Float64(b / c) * -0.5)))
      end
      
      code[a_, b_, c_] := N[(0.5 / N[(a * N[(a * N[(0.5 * N[(c / N[Power[b, 3.0], $MachinePrecision]), $MachinePrecision] + N[(N[(N[(c * c), $MachinePrecision] * a), $MachinePrecision] / N[Power[b, 5.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + N[(0.5 / b), $MachinePrecision]), $MachinePrecision] + N[(N[(b / c), $MachinePrecision] * -0.5), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
      
      \begin{array}{l}
      
      \\
      \frac{0.5}{\mathsf{fma}\left(a, \mathsf{fma}\left(a, \mathsf{fma}\left(0.5, \frac{c}{{b}^{3}}, \frac{\left(c \cdot c\right) \cdot a}{{b}^{5}}\right), \frac{0.5}{b}\right), \frac{b}{c} \cdot -0.5\right)}
      \end{array}
      
      Derivation
      1. Initial program 29.0%

        \[\frac{\left(-b\right) + \sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c}}{2 \cdot a} \]
      2. Add Preprocessing
      3. Step-by-step derivation
        1. lift-/.f64N/A

          \[\leadsto \color{blue}{\frac{\left(-b\right) + \sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c}}{2 \cdot a}} \]
        2. clear-numN/A

          \[\leadsto \color{blue}{\frac{1}{\frac{2 \cdot a}{\left(-b\right) + \sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c}}}} \]
        3. lift-*.f64N/A

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

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

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

          \[\leadsto \frac{\color{blue}{\frac{1}{2}}}{\frac{a}{\left(-b\right) + \sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c}}} \]
        7. lower-/.f64N/A

          \[\leadsto \color{blue}{\frac{\frac{1}{2}}{\frac{a}{\left(-b\right) + \sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c}}}} \]
        8. lower-/.f6429.0

          \[\leadsto \frac{0.5}{\color{blue}{\frac{a}{\left(-b\right) + \sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c}}}} \]
        9. lift-+.f64N/A

          \[\leadsto \frac{\frac{1}{2}}{\frac{a}{\color{blue}{\left(-b\right) + \sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c}}}} \]
        10. +-commutativeN/A

          \[\leadsto \frac{\frac{1}{2}}{\frac{a}{\color{blue}{\sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c} + \left(-b\right)}}} \]
        11. lift-neg.f64N/A

          \[\leadsto \frac{\frac{1}{2}}{\frac{a}{\sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c} + \color{blue}{\left(\mathsf{neg}\left(b\right)\right)}}} \]
        12. unsub-negN/A

          \[\leadsto \frac{\frac{1}{2}}{\frac{a}{\color{blue}{\sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c} - b}}} \]
        13. lower--.f6429.0

          \[\leadsto \frac{0.5}{\frac{a}{\color{blue}{\sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c} - b}}} \]
      4. Applied rewrites29.0%

        \[\leadsto \color{blue}{\frac{0.5}{\frac{a}{\sqrt{\mathsf{fma}\left(-4 \cdot c, a, b \cdot b\right)} - b}}} \]
      5. Taylor expanded in c around 0

        \[\leadsto \frac{\frac{1}{2}}{\color{blue}{\frac{\frac{-1}{2} \cdot b + c \cdot \left(c \cdot \left(-1 \cdot \left(c \cdot \left(-1 \cdot \frac{a \cdot \left(-1 \cdot \frac{{a}^{2}}{{b}^{3}} + \frac{1}{2} \cdot \frac{{a}^{2}}{{b}^{3}}\right)}{{b}^{2}} + \left(\frac{-1}{8} \cdot \frac{b \cdot \left(4 \cdot \frac{{a}^{4}}{{b}^{6}} + 16 \cdot \frac{{a}^{4}}{{b}^{6}}\right)}{a} + \frac{{a}^{3}}{{b}^{5}}\right)\right)\right) - \left(-1 \cdot \frac{{a}^{2}}{{b}^{3}} + \frac{1}{2} \cdot \frac{{a}^{2}}{{b}^{3}}\right)\right) - \frac{-1}{2} \cdot \frac{a}{b}\right)}{c}}} \]
      6. Applied rewrites96.4%

        \[\leadsto \frac{0.5}{\color{blue}{\frac{\mathsf{fma}\left(\mathsf{fma}\left(\mathsf{fma}\left(-c, \mathsf{fma}\left(b \cdot \frac{\frac{{a}^{4}}{{b}^{6}} \cdot 20}{a}, -0.125, \frac{{a}^{3}}{{b}^{5}}\right) - \frac{\frac{a \cdot a}{{b}^{3}} \cdot -0.5}{b} \cdot \frac{a}{b}, \frac{-a \cdot a}{{b}^{3}} \cdot -0.5\right), c, \frac{a}{b} \cdot 0.5\right), c, -0.5 \cdot b\right)}{c}}} \]
      7. Taylor expanded in a around 0

        \[\leadsto \frac{\frac{1}{2}}{\frac{\mathsf{fma}\left(\mathsf{fma}\left(\mathsf{fma}\left(-c, -1 \cdot \frac{{a}^{3}}{{b}^{5}}, \frac{-a \cdot a}{{b}^{3}} \cdot \frac{-1}{2}\right), c, \frac{a}{b} \cdot \frac{1}{2}\right), c, \frac{-1}{2} \cdot b\right)}{c}} \]
      8. Step-by-step derivation
        1. Applied rewrites96.4%

          \[\leadsto \frac{0.5}{\frac{\mathsf{fma}\left(\mathsf{fma}\left(\mathsf{fma}\left(-c, \frac{-{a}^{3}}{{b}^{5}}, \frac{-a \cdot a}{{b}^{3}} \cdot -0.5\right), c, \frac{a}{b} \cdot 0.5\right), c, -0.5 \cdot b\right)}{c}} \]
        2. Taylor expanded in a around 0

          \[\leadsto \frac{\frac{1}{2}}{\frac{-1}{2} \cdot \frac{b}{c} + \color{blue}{a \cdot \left(a \cdot \left(\frac{1}{2} \cdot \frac{c}{{b}^{3}} + \frac{a \cdot {c}^{2}}{{b}^{5}}\right) + \frac{1}{2} \cdot \frac{1}{b}\right)}} \]
        3. Step-by-step derivation
          1. Applied rewrites96.4%

            \[\leadsto \frac{0.5}{\mathsf{fma}\left(a, \color{blue}{\mathsf{fma}\left(a, \mathsf{fma}\left(0.5, \frac{c}{{b}^{3}}, \frac{a \cdot \left(c \cdot c\right)}{{b}^{5}}\right), \frac{0.5}{b}\right)}, -0.5 \cdot \frac{b}{c}\right)} \]
          2. Final simplification96.4%

            \[\leadsto \frac{0.5}{\mathsf{fma}\left(a, \mathsf{fma}\left(a, \mathsf{fma}\left(0.5, \frac{c}{{b}^{3}}, \frac{\left(c \cdot c\right) \cdot a}{{b}^{5}}\right), \frac{0.5}{b}\right), \frac{b}{c} \cdot -0.5\right)} \]
          3. Add Preprocessing

          Alternative 3: 93.8% accurate, 0.3× speedup?

          \[\begin{array}{l} \\ \frac{0.5}{\frac{\mathsf{fma}\left(c, \left(\left(a \cdot a\right) \cdot \frac{c}{{b}^{3}} + \frac{a}{b}\right) \cdot 0.5, -0.5 \cdot b\right)}{c}} \end{array} \]
          (FPCore (a b c)
           :precision binary64
           (/
            0.5
            (/ (fma c (* (+ (* (* a a) (/ c (pow b 3.0))) (/ a b)) 0.5) (* -0.5 b)) c)))
          double code(double a, double b, double c) {
          	return 0.5 / (fma(c, ((((a * a) * (c / pow(b, 3.0))) + (a / b)) * 0.5), (-0.5 * b)) / c);
          }
          
          function code(a, b, c)
          	return Float64(0.5 / Float64(fma(c, Float64(Float64(Float64(Float64(a * a) * Float64(c / (b ^ 3.0))) + Float64(a / b)) * 0.5), Float64(-0.5 * b)) / c))
          end
          
          code[a_, b_, c_] := N[(0.5 / N[(N[(c * N[(N[(N[(N[(a * a), $MachinePrecision] * N[(c / N[Power[b, 3.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + N[(a / b), $MachinePrecision]), $MachinePrecision] * 0.5), $MachinePrecision] + N[(-0.5 * b), $MachinePrecision]), $MachinePrecision] / c), $MachinePrecision]), $MachinePrecision]
          
          \begin{array}{l}
          
          \\
          \frac{0.5}{\frac{\mathsf{fma}\left(c, \left(\left(a \cdot a\right) \cdot \frac{c}{{b}^{3}} + \frac{a}{b}\right) \cdot 0.5, -0.5 \cdot b\right)}{c}}
          \end{array}
          
          Derivation
          1. Initial program 29.0%

            \[\frac{\left(-b\right) + \sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c}}{2 \cdot a} \]
          2. Add Preprocessing
          3. Step-by-step derivation
            1. lift-/.f64N/A

              \[\leadsto \color{blue}{\frac{\left(-b\right) + \sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c}}{2 \cdot a}} \]
            2. clear-numN/A

              \[\leadsto \color{blue}{\frac{1}{\frac{2 \cdot a}{\left(-b\right) + \sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c}}}} \]
            3. lift-*.f64N/A

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

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

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

              \[\leadsto \frac{\color{blue}{\frac{1}{2}}}{\frac{a}{\left(-b\right) + \sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c}}} \]
            7. lower-/.f64N/A

              \[\leadsto \color{blue}{\frac{\frac{1}{2}}{\frac{a}{\left(-b\right) + \sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c}}}} \]
            8. lower-/.f6429.0

              \[\leadsto \frac{0.5}{\color{blue}{\frac{a}{\left(-b\right) + \sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c}}}} \]
            9. lift-+.f64N/A

              \[\leadsto \frac{\frac{1}{2}}{\frac{a}{\color{blue}{\left(-b\right) + \sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c}}}} \]
            10. +-commutativeN/A

              \[\leadsto \frac{\frac{1}{2}}{\frac{a}{\color{blue}{\sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c} + \left(-b\right)}}} \]
            11. lift-neg.f64N/A

              \[\leadsto \frac{\frac{1}{2}}{\frac{a}{\sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c} + \color{blue}{\left(\mathsf{neg}\left(b\right)\right)}}} \]
            12. unsub-negN/A

              \[\leadsto \frac{\frac{1}{2}}{\frac{a}{\color{blue}{\sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c} - b}}} \]
            13. lower--.f6429.0

              \[\leadsto \frac{0.5}{\frac{a}{\color{blue}{\sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c} - b}}} \]
          4. Applied rewrites29.0%

            \[\leadsto \color{blue}{\frac{0.5}{\frac{a}{\sqrt{\mathsf{fma}\left(-4 \cdot c, a, b \cdot b\right)} - b}}} \]
          5. Taylor expanded in c around 0

            \[\leadsto \frac{\frac{1}{2}}{\color{blue}{\frac{\frac{-1}{2} \cdot b + c \cdot \left(c \cdot \left(-1 \cdot \left(c \cdot \left(-1 \cdot \frac{a \cdot \left(-1 \cdot \frac{{a}^{2}}{{b}^{3}} + \frac{1}{2} \cdot \frac{{a}^{2}}{{b}^{3}}\right)}{{b}^{2}} + \left(\frac{-1}{8} \cdot \frac{b \cdot \left(4 \cdot \frac{{a}^{4}}{{b}^{6}} + 16 \cdot \frac{{a}^{4}}{{b}^{6}}\right)}{a} + \frac{{a}^{3}}{{b}^{5}}\right)\right)\right) - \left(-1 \cdot \frac{{a}^{2}}{{b}^{3}} + \frac{1}{2} \cdot \frac{{a}^{2}}{{b}^{3}}\right)\right) - \frac{-1}{2} \cdot \frac{a}{b}\right)}{c}}} \]
          6. Applied rewrites96.4%

            \[\leadsto \frac{0.5}{\color{blue}{\frac{\mathsf{fma}\left(\mathsf{fma}\left(\mathsf{fma}\left(-c, \mathsf{fma}\left(b \cdot \frac{\frac{{a}^{4}}{{b}^{6}} \cdot 20}{a}, -0.125, \frac{{a}^{3}}{{b}^{5}}\right) - \frac{\frac{a \cdot a}{{b}^{3}} \cdot -0.5}{b} \cdot \frac{a}{b}, \frac{-a \cdot a}{{b}^{3}} \cdot -0.5\right), c, \frac{a}{b} \cdot 0.5\right), c, -0.5 \cdot b\right)}{c}}} \]
          7. Taylor expanded in a around 0

            \[\leadsto \frac{\frac{1}{2}}{\frac{\mathsf{fma}\left(\mathsf{fma}\left(\mathsf{fma}\left(-c, -1 \cdot \frac{{a}^{3}}{{b}^{5}}, \frac{-a \cdot a}{{b}^{3}} \cdot \frac{-1}{2}\right), c, \frac{a}{b} \cdot \frac{1}{2}\right), c, \frac{-1}{2} \cdot b\right)}{c}} \]
          8. Step-by-step derivation
            1. Applied rewrites96.4%

              \[\leadsto \frac{0.5}{\frac{\mathsf{fma}\left(\mathsf{fma}\left(\mathsf{fma}\left(-c, \frac{-{a}^{3}}{{b}^{5}}, \frac{-a \cdot a}{{b}^{3}} \cdot -0.5\right), c, \frac{a}{b} \cdot 0.5\right), c, -0.5 \cdot b\right)}{c}} \]
            2. Taylor expanded in c around 0

              \[\leadsto \frac{\frac{1}{2}}{\frac{\frac{-1}{2} \cdot b + c \cdot \left(\frac{1}{2} \cdot \frac{a}{b} + \frac{1}{2} \cdot \frac{{a}^{2} \cdot c}{{b}^{3}}\right)}{\color{blue}{c}}} \]
            3. Step-by-step derivation
              1. Applied rewrites94.7%

                \[\leadsto \frac{0.5}{\frac{\mathsf{fma}\left(c, 0.5 \cdot \left(\frac{a}{b} + \left(a \cdot a\right) \cdot \frac{c}{{b}^{3}}\right), -0.5 \cdot b\right)}{\color{blue}{c}}} \]
              2. Final simplification94.7%

                \[\leadsto \frac{0.5}{\frac{\mathsf{fma}\left(c, \left(\left(a \cdot a\right) \cdot \frac{c}{{b}^{3}} + \frac{a}{b}\right) \cdot 0.5, -0.5 \cdot b\right)}{c}} \]
              3. Add Preprocessing

              Alternative 4: 93.8% accurate, 0.3× speedup?

              \[\begin{array}{l} \\ \frac{0.5}{\mathsf{fma}\left(\mathsf{fma}\left(-a, \frac{c}{{b}^{3}} \cdot -0.5, \frac{0.5}{b}\right), a, \frac{b}{c} \cdot -0.5\right)} \end{array} \]
              (FPCore (a b c)
               :precision binary64
               (/
                0.5
                (fma (fma (- a) (* (/ c (pow b 3.0)) -0.5) (/ 0.5 b)) a (* (/ b c) -0.5))))
              double code(double a, double b, double c) {
              	return 0.5 / fma(fma(-a, ((c / pow(b, 3.0)) * -0.5), (0.5 / b)), a, ((b / c) * -0.5));
              }
              
              function code(a, b, c)
              	return Float64(0.5 / fma(fma(Float64(-a), Float64(Float64(c / (b ^ 3.0)) * -0.5), Float64(0.5 / b)), a, Float64(Float64(b / c) * -0.5)))
              end
              
              code[a_, b_, c_] := N[(0.5 / N[(N[((-a) * N[(N[(c / N[Power[b, 3.0], $MachinePrecision]), $MachinePrecision] * -0.5), $MachinePrecision] + N[(0.5 / b), $MachinePrecision]), $MachinePrecision] * a + N[(N[(b / c), $MachinePrecision] * -0.5), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
              
              \begin{array}{l}
              
              \\
              \frac{0.5}{\mathsf{fma}\left(\mathsf{fma}\left(-a, \frac{c}{{b}^{3}} \cdot -0.5, \frac{0.5}{b}\right), a, \frac{b}{c} \cdot -0.5\right)}
              \end{array}
              
              Derivation
              1. Initial program 29.0%

                \[\frac{\left(-b\right) + \sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c}}{2 \cdot a} \]
              2. Add Preprocessing
              3. Step-by-step derivation
                1. lift-/.f64N/A

                  \[\leadsto \color{blue}{\frac{\left(-b\right) + \sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c}}{2 \cdot a}} \]
                2. clear-numN/A

                  \[\leadsto \color{blue}{\frac{1}{\frac{2 \cdot a}{\left(-b\right) + \sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c}}}} \]
                3. lift-*.f64N/A

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

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

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

                  \[\leadsto \frac{\color{blue}{\frac{1}{2}}}{\frac{a}{\left(-b\right) + \sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c}}} \]
                7. lower-/.f64N/A

                  \[\leadsto \color{blue}{\frac{\frac{1}{2}}{\frac{a}{\left(-b\right) + \sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c}}}} \]
                8. lower-/.f6429.0

                  \[\leadsto \frac{0.5}{\color{blue}{\frac{a}{\left(-b\right) + \sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c}}}} \]
                9. lift-+.f64N/A

                  \[\leadsto \frac{\frac{1}{2}}{\frac{a}{\color{blue}{\left(-b\right) + \sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c}}}} \]
                10. +-commutativeN/A

                  \[\leadsto \frac{\frac{1}{2}}{\frac{a}{\color{blue}{\sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c} + \left(-b\right)}}} \]
                11. lift-neg.f64N/A

                  \[\leadsto \frac{\frac{1}{2}}{\frac{a}{\sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c} + \color{blue}{\left(\mathsf{neg}\left(b\right)\right)}}} \]
                12. unsub-negN/A

                  \[\leadsto \frac{\frac{1}{2}}{\frac{a}{\color{blue}{\sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c} - b}}} \]
                13. lower--.f6429.0

                  \[\leadsto \frac{0.5}{\frac{a}{\color{blue}{\sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c} - b}}} \]
              4. Applied rewrites29.0%

                \[\leadsto \color{blue}{\frac{0.5}{\frac{a}{\sqrt{\mathsf{fma}\left(-4 \cdot c, a, b \cdot b\right)} - b}}} \]
              5. Taylor expanded in a around 0

                \[\leadsto \frac{\frac{1}{2}}{\color{blue}{\frac{-1}{2} \cdot \frac{b}{c} + a \cdot \left(-1 \cdot \left(a \cdot \left(-1 \cdot \frac{c}{{b}^{3}} + \frac{1}{2} \cdot \frac{c}{{b}^{3}}\right)\right) + \frac{1}{2} \cdot \frac{1}{b}\right)}} \]
              6. Step-by-step derivation
                1. +-commutativeN/A

                  \[\leadsto \frac{\frac{1}{2}}{\color{blue}{a \cdot \left(-1 \cdot \left(a \cdot \left(-1 \cdot \frac{c}{{b}^{3}} + \frac{1}{2} \cdot \frac{c}{{b}^{3}}\right)\right) + \frac{1}{2} \cdot \frac{1}{b}\right) + \frac{-1}{2} \cdot \frac{b}{c}}} \]
                2. *-commutativeN/A

                  \[\leadsto \frac{\frac{1}{2}}{\color{blue}{\left(-1 \cdot \left(a \cdot \left(-1 \cdot \frac{c}{{b}^{3}} + \frac{1}{2} \cdot \frac{c}{{b}^{3}}\right)\right) + \frac{1}{2} \cdot \frac{1}{b}\right) \cdot a} + \frac{-1}{2} \cdot \frac{b}{c}} \]
                3. lower-fma.f64N/A

                  \[\leadsto \frac{\frac{1}{2}}{\color{blue}{\mathsf{fma}\left(-1 \cdot \left(a \cdot \left(-1 \cdot \frac{c}{{b}^{3}} + \frac{1}{2} \cdot \frac{c}{{b}^{3}}\right)\right) + \frac{1}{2} \cdot \frac{1}{b}, a, \frac{-1}{2} \cdot \frac{b}{c}\right)}} \]
              7. Applied rewrites94.7%

                \[\leadsto \frac{0.5}{\color{blue}{\mathsf{fma}\left(\mathsf{fma}\left(-a, \frac{c}{{b}^{3}} \cdot -0.5, \frac{0.5}{b}\right), a, \frac{b}{c} \cdot -0.5\right)}} \]
              8. Add Preprocessing

              Alternative 5: 93.8% accurate, 0.3× speedup?

              \[\begin{array}{l} \\ \frac{0.5}{\mathsf{fma}\left(-0.5, \frac{b}{c}, \mathsf{fma}\left(0.5, \frac{c}{{b}^{3}} \cdot a, \frac{0.5}{b}\right) \cdot a\right)} \end{array} \]
              (FPCore (a b c)
               :precision binary64
               (/ 0.5 (fma -0.5 (/ b c) (* (fma 0.5 (* (/ c (pow b 3.0)) a) (/ 0.5 b)) a))))
              double code(double a, double b, double c) {
              	return 0.5 / fma(-0.5, (b / c), (fma(0.5, ((c / pow(b, 3.0)) * a), (0.5 / b)) * a));
              }
              
              function code(a, b, c)
              	return Float64(0.5 / fma(-0.5, Float64(b / c), Float64(fma(0.5, Float64(Float64(c / (b ^ 3.0)) * a), Float64(0.5 / b)) * a)))
              end
              
              code[a_, b_, c_] := N[(0.5 / N[(-0.5 * N[(b / c), $MachinePrecision] + N[(N[(0.5 * N[(N[(c / N[Power[b, 3.0], $MachinePrecision]), $MachinePrecision] * a), $MachinePrecision] + N[(0.5 / b), $MachinePrecision]), $MachinePrecision] * a), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
              
              \begin{array}{l}
              
              \\
              \frac{0.5}{\mathsf{fma}\left(-0.5, \frac{b}{c}, \mathsf{fma}\left(0.5, \frac{c}{{b}^{3}} \cdot a, \frac{0.5}{b}\right) \cdot a\right)}
              \end{array}
              
              Derivation
              1. Initial program 29.0%

                \[\frac{\left(-b\right) + \sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c}}{2 \cdot a} \]
              2. Add Preprocessing
              3. Step-by-step derivation
                1. lift-/.f64N/A

                  \[\leadsto \color{blue}{\frac{\left(-b\right) + \sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c}}{2 \cdot a}} \]
                2. clear-numN/A

                  \[\leadsto \color{blue}{\frac{1}{\frac{2 \cdot a}{\left(-b\right) + \sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c}}}} \]
                3. lift-*.f64N/A

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

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

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

                  \[\leadsto \frac{\color{blue}{\frac{1}{2}}}{\frac{a}{\left(-b\right) + \sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c}}} \]
                7. lower-/.f64N/A

                  \[\leadsto \color{blue}{\frac{\frac{1}{2}}{\frac{a}{\left(-b\right) + \sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c}}}} \]
                8. lower-/.f6429.0

                  \[\leadsto \frac{0.5}{\color{blue}{\frac{a}{\left(-b\right) + \sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c}}}} \]
                9. lift-+.f64N/A

                  \[\leadsto \frac{\frac{1}{2}}{\frac{a}{\color{blue}{\left(-b\right) + \sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c}}}} \]
                10. +-commutativeN/A

                  \[\leadsto \frac{\frac{1}{2}}{\frac{a}{\color{blue}{\sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c} + \left(-b\right)}}} \]
                11. lift-neg.f64N/A

                  \[\leadsto \frac{\frac{1}{2}}{\frac{a}{\sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c} + \color{blue}{\left(\mathsf{neg}\left(b\right)\right)}}} \]
                12. unsub-negN/A

                  \[\leadsto \frac{\frac{1}{2}}{\frac{a}{\color{blue}{\sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c} - b}}} \]
                13. lower--.f6429.0

                  \[\leadsto \frac{0.5}{\frac{a}{\color{blue}{\sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c} - b}}} \]
              4. Applied rewrites29.0%

                \[\leadsto \color{blue}{\frac{0.5}{\frac{a}{\sqrt{\mathsf{fma}\left(-4 \cdot c, a, b \cdot b\right)} - b}}} \]
              5. Taylor expanded in c around 0

                \[\leadsto \frac{\frac{1}{2}}{\color{blue}{\frac{\frac{-1}{2} \cdot b + c \cdot \left(c \cdot \left(-1 \cdot \left(c \cdot \left(-1 \cdot \frac{a \cdot \left(-1 \cdot \frac{{a}^{2}}{{b}^{3}} + \frac{1}{2} \cdot \frac{{a}^{2}}{{b}^{3}}\right)}{{b}^{2}} + \left(\frac{-1}{8} \cdot \frac{b \cdot \left(4 \cdot \frac{{a}^{4}}{{b}^{6}} + 16 \cdot \frac{{a}^{4}}{{b}^{6}}\right)}{a} + \frac{{a}^{3}}{{b}^{5}}\right)\right)\right) - \left(-1 \cdot \frac{{a}^{2}}{{b}^{3}} + \frac{1}{2} \cdot \frac{{a}^{2}}{{b}^{3}}\right)\right) - \frac{-1}{2} \cdot \frac{a}{b}\right)}{c}}} \]
              6. Applied rewrites96.4%

                \[\leadsto \frac{0.5}{\color{blue}{\frac{\mathsf{fma}\left(\mathsf{fma}\left(\mathsf{fma}\left(-c, \mathsf{fma}\left(b \cdot \frac{\frac{{a}^{4}}{{b}^{6}} \cdot 20}{a}, -0.125, \frac{{a}^{3}}{{b}^{5}}\right) - \frac{\frac{a \cdot a}{{b}^{3}} \cdot -0.5}{b} \cdot \frac{a}{b}, \frac{-a \cdot a}{{b}^{3}} \cdot -0.5\right), c, \frac{a}{b} \cdot 0.5\right), c, -0.5 \cdot b\right)}{c}}} \]
              7. Taylor expanded in a around 0

                \[\leadsto \frac{\frac{1}{2}}{\frac{\mathsf{fma}\left(\mathsf{fma}\left(\mathsf{fma}\left(-c, -1 \cdot \frac{{a}^{3}}{{b}^{5}}, \frac{-a \cdot a}{{b}^{3}} \cdot \frac{-1}{2}\right), c, \frac{a}{b} \cdot \frac{1}{2}\right), c, \frac{-1}{2} \cdot b\right)}{c}} \]
              8. Step-by-step derivation
                1. Applied rewrites96.4%

                  \[\leadsto \frac{0.5}{\frac{\mathsf{fma}\left(\mathsf{fma}\left(\mathsf{fma}\left(-c, \frac{-{a}^{3}}{{b}^{5}}, \frac{-a \cdot a}{{b}^{3}} \cdot -0.5\right), c, \frac{a}{b} \cdot 0.5\right), c, -0.5 \cdot b\right)}{c}} \]
                2. Taylor expanded in a around 0

                  \[\leadsto \frac{\frac{1}{2}}{\frac{-1}{2} \cdot \frac{b}{c} + \color{blue}{a \cdot \left(\frac{1}{2} \cdot \frac{a \cdot c}{{b}^{3}} + \frac{1}{2} \cdot \frac{1}{b}\right)}} \]
                3. Step-by-step derivation
                  1. Applied rewrites94.7%

                    \[\leadsto \frac{0.5}{\mathsf{fma}\left(-0.5, \color{blue}{\frac{b}{c}}, a \cdot \mathsf{fma}\left(0.5, a \cdot \frac{c}{{b}^{3}}, \frac{0.5}{b}\right)\right)} \]
                  2. Final simplification94.7%

                    \[\leadsto \frac{0.5}{\mathsf{fma}\left(-0.5, \frac{b}{c}, \mathsf{fma}\left(0.5, \frac{c}{{b}^{3}} \cdot a, \frac{0.5}{b}\right) \cdot a\right)} \]
                  3. Add Preprocessing

                  Alternative 6: 90.7% accurate, 1.1× speedup?

                  \[\begin{array}{l} \\ \frac{0.5}{\mathsf{fma}\left(\frac{a}{b}, 0.5, \frac{b}{c} \cdot -0.5\right)} \end{array} \]
                  (FPCore (a b c) :precision binary64 (/ 0.5 (fma (/ a b) 0.5 (* (/ b c) -0.5))))
                  double code(double a, double b, double c) {
                  	return 0.5 / fma((a / b), 0.5, ((b / c) * -0.5));
                  }
                  
                  function code(a, b, c)
                  	return Float64(0.5 / fma(Float64(a / b), 0.5, Float64(Float64(b / c) * -0.5)))
                  end
                  
                  code[a_, b_, c_] := N[(0.5 / N[(N[(a / b), $MachinePrecision] * 0.5 + N[(N[(b / c), $MachinePrecision] * -0.5), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
                  
                  \begin{array}{l}
                  
                  \\
                  \frac{0.5}{\mathsf{fma}\left(\frac{a}{b}, 0.5, \frac{b}{c} \cdot -0.5\right)}
                  \end{array}
                  
                  Derivation
                  1. Initial program 29.0%

                    \[\frac{\left(-b\right) + \sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c}}{2 \cdot a} \]
                  2. Add Preprocessing
                  3. Step-by-step derivation
                    1. lift-/.f64N/A

                      \[\leadsto \color{blue}{\frac{\left(-b\right) + \sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c}}{2 \cdot a}} \]
                    2. clear-numN/A

                      \[\leadsto \color{blue}{\frac{1}{\frac{2 \cdot a}{\left(-b\right) + \sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c}}}} \]
                    3. lift-*.f64N/A

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

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

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

                      \[\leadsto \frac{\color{blue}{\frac{1}{2}}}{\frac{a}{\left(-b\right) + \sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c}}} \]
                    7. lower-/.f64N/A

                      \[\leadsto \color{blue}{\frac{\frac{1}{2}}{\frac{a}{\left(-b\right) + \sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c}}}} \]
                    8. lower-/.f6429.0

                      \[\leadsto \frac{0.5}{\color{blue}{\frac{a}{\left(-b\right) + \sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c}}}} \]
                    9. lift-+.f64N/A

                      \[\leadsto \frac{\frac{1}{2}}{\frac{a}{\color{blue}{\left(-b\right) + \sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c}}}} \]
                    10. +-commutativeN/A

                      \[\leadsto \frac{\frac{1}{2}}{\frac{a}{\color{blue}{\sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c} + \left(-b\right)}}} \]
                    11. lift-neg.f64N/A

                      \[\leadsto \frac{\frac{1}{2}}{\frac{a}{\sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c} + \color{blue}{\left(\mathsf{neg}\left(b\right)\right)}}} \]
                    12. unsub-negN/A

                      \[\leadsto \frac{\frac{1}{2}}{\frac{a}{\color{blue}{\sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c} - b}}} \]
                    13. lower--.f6429.0

                      \[\leadsto \frac{0.5}{\frac{a}{\color{blue}{\sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c} - b}}} \]
                  4. Applied rewrites29.0%

                    \[\leadsto \color{blue}{\frac{0.5}{\frac{a}{\sqrt{\mathsf{fma}\left(-4 \cdot c, a, b \cdot b\right)} - b}}} \]
                  5. Taylor expanded in a around 0

                    \[\leadsto \frac{\frac{1}{2}}{\color{blue}{\frac{-1}{2} \cdot \frac{b}{c} + \frac{1}{2} \cdot \frac{a}{b}}} \]
                  6. Step-by-step derivation
                    1. +-commutativeN/A

                      \[\leadsto \frac{\frac{1}{2}}{\color{blue}{\frac{1}{2} \cdot \frac{a}{b} + \frac{-1}{2} \cdot \frac{b}{c}}} \]
                    2. *-commutativeN/A

                      \[\leadsto \frac{\frac{1}{2}}{\color{blue}{\frac{a}{b} \cdot \frac{1}{2}} + \frac{-1}{2} \cdot \frac{b}{c}} \]
                    3. lower-fma.f64N/A

                      \[\leadsto \frac{\frac{1}{2}}{\color{blue}{\mathsf{fma}\left(\frac{a}{b}, \frac{1}{2}, \frac{-1}{2} \cdot \frac{b}{c}\right)}} \]
                    4. lower-/.f64N/A

                      \[\leadsto \frac{\frac{1}{2}}{\mathsf{fma}\left(\color{blue}{\frac{a}{b}}, \frac{1}{2}, \frac{-1}{2} \cdot \frac{b}{c}\right)} \]
                    5. *-commutativeN/A

                      \[\leadsto \frac{\frac{1}{2}}{\mathsf{fma}\left(\frac{a}{b}, \frac{1}{2}, \color{blue}{\frac{b}{c} \cdot \frac{-1}{2}}\right)} \]
                    6. lower-*.f64N/A

                      \[\leadsto \frac{\frac{1}{2}}{\mathsf{fma}\left(\frac{a}{b}, \frac{1}{2}, \color{blue}{\frac{b}{c} \cdot \frac{-1}{2}}\right)} \]
                    7. lower-/.f6491.7

                      \[\leadsto \frac{0.5}{\mathsf{fma}\left(\frac{a}{b}, 0.5, \color{blue}{\frac{b}{c}} \cdot -0.5\right)} \]
                  7. Applied rewrites91.7%

                    \[\leadsto \frac{0.5}{\color{blue}{\mathsf{fma}\left(\frac{a}{b}, 0.5, \frac{b}{c} \cdot -0.5\right)}} \]
                  8. Add Preprocessing

                  Alternative 7: 81.1% accurate, 3.6× speedup?

                  \[\begin{array}{l} \\ \frac{-c}{b} \end{array} \]
                  (FPCore (a b c) :precision binary64 (/ (- c) b))
                  double code(double a, double b, double c) {
                  	return -c / b;
                  }
                  
                  real(8) function code(a, b, c)
                      real(8), intent (in) :: a
                      real(8), intent (in) :: b
                      real(8), intent (in) :: c
                      code = -c / b
                  end function
                  
                  public static double code(double a, double b, double c) {
                  	return -c / b;
                  }
                  
                  def code(a, b, c):
                  	return -c / b
                  
                  function code(a, b, c)
                  	return Float64(Float64(-c) / b)
                  end
                  
                  function tmp = code(a, b, c)
                  	tmp = -c / b;
                  end
                  
                  code[a_, b_, c_] := N[((-c) / b), $MachinePrecision]
                  
                  \begin{array}{l}
                  
                  \\
                  \frac{-c}{b}
                  \end{array}
                  
                  Derivation
                  1. Initial program 29.0%

                    \[\frac{\left(-b\right) + \sqrt{b \cdot b - \left(4 \cdot a\right) \cdot c}}{2 \cdot a} \]
                  2. Add Preprocessing
                  3. Taylor expanded in a around 0

                    \[\leadsto \color{blue}{-1 \cdot \frac{c}{b}} \]
                  4. Step-by-step derivation
                    1. associate-*r/N/A

                      \[\leadsto \color{blue}{\frac{-1 \cdot c}{b}} \]
                    2. lower-/.f64N/A

                      \[\leadsto \color{blue}{\frac{-1 \cdot c}{b}} \]
                    3. mul-1-negN/A

                      \[\leadsto \frac{\color{blue}{\mathsf{neg}\left(c\right)}}{b} \]
                    4. lower-neg.f6483.1

                      \[\leadsto \frac{\color{blue}{-c}}{b} \]
                  5. Applied rewrites83.1%

                    \[\leadsto \color{blue}{\frac{-c}{b}} \]
                  6. Add Preprocessing

                  Reproduce

                  ?
                  herbie shell --seed 2024288 
                  (FPCore (a b c)
                    :name "Quadratic roots, medium range"
                    :precision binary64
                    :pre (and (and (and (< 1.1102230246251565e-16 a) (< a 9007199254740992.0)) (and (< 1.1102230246251565e-16 b) (< b 9007199254740992.0))) (and (< 1.1102230246251565e-16 c) (< c 9007199254740992.0)))
                    (/ (+ (- b) (sqrt (- (* b b) (* (* 4.0 a) c)))) (* 2.0 a)))