Cubic critical, wide range

Percentage Accurate: 17.6% → 97.8%
Time: 14.1s
Alternatives: 10
Speedup: 2.9×

Specification

?
\[\left(\left(4.930380657631324 \cdot 10^{-32} < a \land a < 2.028240960365167 \cdot 10^{+31}\right) \land \left(4.930380657631324 \cdot 10^{-32} < b \land b < 2.028240960365167 \cdot 10^{+31}\right)\right) \land \left(4.930380657631324 \cdot 10^{-32} < c \land c < 2.028240960365167 \cdot 10^{+31}\right)\]
\[\begin{array}{l} \\ \frac{\left(-b\right) + \sqrt{b \cdot b - \left(3 \cdot a\right) \cdot c}}{3 \cdot a} \end{array} \]
(FPCore (a b c)
 :precision binary64
 (/ (+ (- b) (sqrt (- (* b b) (* (* 3.0 a) c)))) (* 3.0 a)))
double code(double a, double b, double c) {
	return (-b + sqrt(((b * b) - ((3.0 * a) * c)))) / (3.0 * 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) - ((3.0d0 * a) * c)))) / (3.0d0 * a)
end function
public static double code(double a, double b, double c) {
	return (-b + Math.sqrt(((b * b) - ((3.0 * a) * c)))) / (3.0 * a);
}
def code(a, b, c):
	return (-b + math.sqrt(((b * b) - ((3.0 * a) * c)))) / (3.0 * a)
function code(a, b, c)
	return Float64(Float64(Float64(-b) + sqrt(Float64(Float64(b * b) - Float64(Float64(3.0 * a) * c)))) / Float64(3.0 * a))
end
function tmp = code(a, b, c)
	tmp = (-b + sqrt(((b * b) - ((3.0 * a) * c)))) / (3.0 * a);
end
code[a_, b_, c_] := N[(N[((-b) + N[Sqrt[N[(N[(b * b), $MachinePrecision] - N[(N[(3.0 * a), $MachinePrecision] * c), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] / N[(3.0 * a), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\frac{\left(-b\right) + \sqrt{b \cdot b - \left(3 \cdot a\right) \cdot c}}{3 \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 10 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: 17.6% accurate, 1.0× speedup?

\[\begin{array}{l} \\ \frac{\left(-b\right) + \sqrt{b \cdot b - \left(3 \cdot a\right) \cdot c}}{3 \cdot a} \end{array} \]
(FPCore (a b c)
 :precision binary64
 (/ (+ (- b) (sqrt (- (* b b) (* (* 3.0 a) c)))) (* 3.0 a)))
double code(double a, double b, double c) {
	return (-b + sqrt(((b * b) - ((3.0 * a) * c)))) / (3.0 * 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) - ((3.0d0 * a) * c)))) / (3.0d0 * a)
end function
public static double code(double a, double b, double c) {
	return (-b + Math.sqrt(((b * b) - ((3.0 * a) * c)))) / (3.0 * a);
}
def code(a, b, c):
	return (-b + math.sqrt(((b * b) - ((3.0 * a) * c)))) / (3.0 * a)
function code(a, b, c)
	return Float64(Float64(Float64(-b) + sqrt(Float64(Float64(b * b) - Float64(Float64(3.0 * a) * c)))) / Float64(3.0 * a))
end
function tmp = code(a, b, c)
	tmp = (-b + sqrt(((b * b) - ((3.0 * a) * c)))) / (3.0 * a);
end
code[a_, b_, c_] := N[(N[((-b) + N[Sqrt[N[(N[(b * b), $MachinePrecision] - N[(N[(3.0 * a), $MachinePrecision] * c), $MachinePrecision]), $MachinePrecision]], $MachinePrecision]), $MachinePrecision] / N[(3.0 * a), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\frac{\left(-b\right) + \sqrt{b \cdot b - \left(3 \cdot a\right) \cdot c}}{3 \cdot a}
\end{array}

Alternative 1: 97.8% accurate, 0.2× speedup?

\[\begin{array}{l} \\ \mathsf{fma}\left(\frac{c}{b}, -0.5, \left(\mathsf{fma}\left(\left(\mathsf{fma}\left(c \cdot a, -0.5625, \left(b \cdot b\right) \cdot -0.375\right) \cdot c\right) \cdot c, b \cdot b, {c}^{4} \cdot \left(-1.0546875 \cdot \left(a \cdot a\right)\right)\right) \cdot {b}^{-7}\right) \cdot a\right) \end{array} \]
(FPCore (a b c)
 :precision binary64
 (fma
  (/ c b)
  -0.5
  (*
   (*
    (fma
     (* (* (fma (* c a) -0.5625 (* (* b b) -0.375)) c) c)
     (* b b)
     (* (pow c 4.0) (* -1.0546875 (* a a))))
    (pow b -7.0))
   a)))
double code(double a, double b, double c) {
	return fma((c / b), -0.5, ((fma(((fma((c * a), -0.5625, ((b * b) * -0.375)) * c) * c), (b * b), (pow(c, 4.0) * (-1.0546875 * (a * a)))) * pow(b, -7.0)) * a));
}
function code(a, b, c)
	return fma(Float64(c / b), -0.5, Float64(Float64(fma(Float64(Float64(fma(Float64(c * a), -0.5625, Float64(Float64(b * b) * -0.375)) * c) * c), Float64(b * b), Float64((c ^ 4.0) * Float64(-1.0546875 * Float64(a * a)))) * (b ^ -7.0)) * a))
end
code[a_, b_, c_] := N[(N[(c / b), $MachinePrecision] * -0.5 + N[(N[(N[(N[(N[(N[(N[(c * a), $MachinePrecision] * -0.5625 + N[(N[(b * b), $MachinePrecision] * -0.375), $MachinePrecision]), $MachinePrecision] * c), $MachinePrecision] * c), $MachinePrecision] * N[(b * b), $MachinePrecision] + N[(N[Power[c, 4.0], $MachinePrecision] * N[(-1.0546875 * N[(a * a), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] * N[Power[b, -7.0], $MachinePrecision]), $MachinePrecision] * a), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
\mathsf{fma}\left(\frac{c}{b}, -0.5, \left(\mathsf{fma}\left(\left(\mathsf{fma}\left(c \cdot a, -0.5625, \left(b \cdot b\right) \cdot -0.375\right) \cdot c\right) \cdot c, b \cdot b, {c}^{4} \cdot \left(-1.0546875 \cdot \left(a \cdot a\right)\right)\right) \cdot {b}^{-7}\right) \cdot a\right)
\end{array}
Derivation
  1. Initial program 18.0%

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

    \[\leadsto \color{blue}{\frac{-1}{2} \cdot \frac{c}{b} + a \cdot \left(\frac{-3}{8} \cdot \frac{{c}^{2}}{{b}^{3}} + a \cdot \left(\frac{-9}{16} \cdot \frac{{c}^{3}}{{b}^{5}} + \frac{-1}{6} \cdot \frac{a \cdot \left(\frac{81}{64} \cdot \frac{{c}^{4}}{{b}^{6}} + \frac{81}{16} \cdot \frac{{c}^{4}}{{b}^{6}}\right)}{b}\right)\right)} \]
  4. Step-by-step derivation
    1. +-commutativeN/A

      \[\leadsto \color{blue}{a \cdot \left(\frac{-3}{8} \cdot \frac{{c}^{2}}{{b}^{3}} + a \cdot \left(\frac{-9}{16} \cdot \frac{{c}^{3}}{{b}^{5}} + \frac{-1}{6} \cdot \frac{a \cdot \left(\frac{81}{64} \cdot \frac{{c}^{4}}{{b}^{6}} + \frac{81}{16} \cdot \frac{{c}^{4}}{{b}^{6}}\right)}{b}\right)\right) + \frac{-1}{2} \cdot \frac{c}{b}} \]
    2. *-commutativeN/A

      \[\leadsto \color{blue}{\left(\frac{-3}{8} \cdot \frac{{c}^{2}}{{b}^{3}} + a \cdot \left(\frac{-9}{16} \cdot \frac{{c}^{3}}{{b}^{5}} + \frac{-1}{6} \cdot \frac{a \cdot \left(\frac{81}{64} \cdot \frac{{c}^{4}}{{b}^{6}} + \frac{81}{16} \cdot \frac{{c}^{4}}{{b}^{6}}\right)}{b}\right)\right) \cdot a} + \frac{-1}{2} \cdot \frac{c}{b} \]
    3. lower-fma.f64N/A

      \[\leadsto \color{blue}{\mathsf{fma}\left(\frac{-3}{8} \cdot \frac{{c}^{2}}{{b}^{3}} + a \cdot \left(\frac{-9}{16} \cdot \frac{{c}^{3}}{{b}^{5}} + \frac{-1}{6} \cdot \frac{a \cdot \left(\frac{81}{64} \cdot \frac{{c}^{4}}{{b}^{6}} + \frac{81}{16} \cdot \frac{{c}^{4}}{{b}^{6}}\right)}{b}\right), a, \frac{-1}{2} \cdot \frac{c}{b}\right)} \]
  5. Applied rewrites98.1%

    \[\leadsto \color{blue}{\mathsf{fma}\left(\mathsf{fma}\left(\mathsf{fma}\left(-0.16666666666666666 \cdot a, \frac{{c}^{4}}{{b}^{6}} \cdot \frac{6.328125}{b}, \frac{{c}^{3} \cdot -0.5625}{{b}^{5}}\right), a, \frac{\left(c \cdot c\right) \cdot -0.375}{{b}^{3}}\right), a, \frac{c}{b} \cdot -0.5\right)} \]
  6. Taylor expanded in b around 0

    \[\leadsto \mathsf{fma}\left(\frac{\frac{-135}{128} \cdot \left({a}^{2} \cdot {c}^{4}\right) + {b}^{2} \cdot \left(\frac{-9}{16} \cdot \left(a \cdot {c}^{3}\right) + \frac{-3}{8} \cdot \left({b}^{2} \cdot {c}^{2}\right)\right)}{{b}^{7}}, a, \frac{c}{b} \cdot \frac{-1}{2}\right) \]
  7. Step-by-step derivation
    1. Applied rewrites98.1%

      \[\leadsto \mathsf{fma}\left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\left(b \cdot \left(c \cdot c\right)\right) \cdot b, -0.375, \left({c}^{3} \cdot a\right) \cdot -0.5625\right) \cdot b, b, \left(-1.0546875 \cdot {c}^{4}\right) \cdot \left(a \cdot a\right)\right)}{{b}^{7}}, a, \frac{c}{b} \cdot -0.5\right) \]
    2. Taylor expanded in c around 0

      \[\leadsto \mathsf{fma}\left(\frac{\mathsf{fma}\left(\left({c}^{2} \cdot \left(\frac{-9}{16} \cdot \left(a \cdot c\right) + \frac{-3}{8} \cdot {b}^{2}\right)\right) \cdot b, b, \left(\frac{-135}{128} \cdot {c}^{4}\right) \cdot \left(a \cdot a\right)\right)}{{b}^{7}}, a, \frac{c}{b} \cdot \frac{-1}{2}\right) \]
    3. Step-by-step derivation
      1. Applied rewrites98.1%

        \[\leadsto \mathsf{fma}\left(\frac{\mathsf{fma}\left(\left(\left(c \cdot c\right) \cdot \mathsf{fma}\left(-0.5625, a \cdot c, -0.375 \cdot \left(b \cdot b\right)\right)\right) \cdot b, b, \left(-1.0546875 \cdot {c}^{4}\right) \cdot \left(a \cdot a\right)\right)}{{b}^{7}}, a, \frac{c}{b} \cdot -0.5\right) \]
      2. Applied rewrites98.1%

        \[\leadsto \mathsf{fma}\left(\frac{c}{b}, \color{blue}{-0.5}, \left({b}^{-7} \cdot \mathsf{fma}\left(\left(\mathsf{fma}\left(c \cdot a, -0.5625, \left(b \cdot b\right) \cdot -0.375\right) \cdot c\right) \cdot c, b \cdot b, \left(\left(a \cdot a\right) \cdot -1.0546875\right) \cdot {c}^{4}\right)\right) \cdot a\right) \]
      3. Final simplification98.1%

        \[\leadsto \mathsf{fma}\left(\frac{c}{b}, -0.5, \left(\mathsf{fma}\left(\left(\mathsf{fma}\left(c \cdot a, -0.5625, \left(b \cdot b\right) \cdot -0.375\right) \cdot c\right) \cdot c, b \cdot b, {c}^{4} \cdot \left(-1.0546875 \cdot \left(a \cdot a\right)\right)\right) \cdot {b}^{-7}\right) \cdot a\right) \]
      4. Add Preprocessing

      Alternative 2: 97.5% accurate, 0.2× speedup?

      \[\begin{array}{l} \\ \mathsf{fma}\left(\frac{-0.5}{b}, c, \left(\mathsf{fma}\left(\left(\mathsf{fma}\left(c \cdot a, -0.5625, \left(b \cdot b\right) \cdot -0.375\right) \cdot c\right) \cdot c, b \cdot b, {c}^{4} \cdot \left(-1.0546875 \cdot \left(a \cdot a\right)\right)\right) \cdot {b}^{-7}\right) \cdot a\right) \end{array} \]
      (FPCore (a b c)
       :precision binary64
       (fma
        (/ -0.5 b)
        c
        (*
         (*
          (fma
           (* (* (fma (* c a) -0.5625 (* (* b b) -0.375)) c) c)
           (* b b)
           (* (pow c 4.0) (* -1.0546875 (* a a))))
          (pow b -7.0))
         a)))
      double code(double a, double b, double c) {
      	return fma((-0.5 / b), c, ((fma(((fma((c * a), -0.5625, ((b * b) * -0.375)) * c) * c), (b * b), (pow(c, 4.0) * (-1.0546875 * (a * a)))) * pow(b, -7.0)) * a));
      }
      
      function code(a, b, c)
      	return fma(Float64(-0.5 / b), c, Float64(Float64(fma(Float64(Float64(fma(Float64(c * a), -0.5625, Float64(Float64(b * b) * -0.375)) * c) * c), Float64(b * b), Float64((c ^ 4.0) * Float64(-1.0546875 * Float64(a * a)))) * (b ^ -7.0)) * a))
      end
      
      code[a_, b_, c_] := N[(N[(-0.5 / b), $MachinePrecision] * c + N[(N[(N[(N[(N[(N[(N[(c * a), $MachinePrecision] * -0.5625 + N[(N[(b * b), $MachinePrecision] * -0.375), $MachinePrecision]), $MachinePrecision] * c), $MachinePrecision] * c), $MachinePrecision] * N[(b * b), $MachinePrecision] + N[(N[Power[c, 4.0], $MachinePrecision] * N[(-1.0546875 * N[(a * a), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] * N[Power[b, -7.0], $MachinePrecision]), $MachinePrecision] * a), $MachinePrecision]), $MachinePrecision]
      
      \begin{array}{l}
      
      \\
      \mathsf{fma}\left(\frac{-0.5}{b}, c, \left(\mathsf{fma}\left(\left(\mathsf{fma}\left(c \cdot a, -0.5625, \left(b \cdot b\right) \cdot -0.375\right) \cdot c\right) \cdot c, b \cdot b, {c}^{4} \cdot \left(-1.0546875 \cdot \left(a \cdot a\right)\right)\right) \cdot {b}^{-7}\right) \cdot a\right)
      \end{array}
      
      Derivation
      1. Initial program 18.0%

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

        \[\leadsto \color{blue}{\frac{-1}{2} \cdot \frac{c}{b} + a \cdot \left(\frac{-3}{8} \cdot \frac{{c}^{2}}{{b}^{3}} + a \cdot \left(\frac{-9}{16} \cdot \frac{{c}^{3}}{{b}^{5}} + \frac{-1}{6} \cdot \frac{a \cdot \left(\frac{81}{64} \cdot \frac{{c}^{4}}{{b}^{6}} + \frac{81}{16} \cdot \frac{{c}^{4}}{{b}^{6}}\right)}{b}\right)\right)} \]
      4. Step-by-step derivation
        1. +-commutativeN/A

          \[\leadsto \color{blue}{a \cdot \left(\frac{-3}{8} \cdot \frac{{c}^{2}}{{b}^{3}} + a \cdot \left(\frac{-9}{16} \cdot \frac{{c}^{3}}{{b}^{5}} + \frac{-1}{6} \cdot \frac{a \cdot \left(\frac{81}{64} \cdot \frac{{c}^{4}}{{b}^{6}} + \frac{81}{16} \cdot \frac{{c}^{4}}{{b}^{6}}\right)}{b}\right)\right) + \frac{-1}{2} \cdot \frac{c}{b}} \]
        2. *-commutativeN/A

          \[\leadsto \color{blue}{\left(\frac{-3}{8} \cdot \frac{{c}^{2}}{{b}^{3}} + a \cdot \left(\frac{-9}{16} \cdot \frac{{c}^{3}}{{b}^{5}} + \frac{-1}{6} \cdot \frac{a \cdot \left(\frac{81}{64} \cdot \frac{{c}^{4}}{{b}^{6}} + \frac{81}{16} \cdot \frac{{c}^{4}}{{b}^{6}}\right)}{b}\right)\right) \cdot a} + \frac{-1}{2} \cdot \frac{c}{b} \]
        3. lower-fma.f64N/A

          \[\leadsto \color{blue}{\mathsf{fma}\left(\frac{-3}{8} \cdot \frac{{c}^{2}}{{b}^{3}} + a \cdot \left(\frac{-9}{16} \cdot \frac{{c}^{3}}{{b}^{5}} + \frac{-1}{6} \cdot \frac{a \cdot \left(\frac{81}{64} \cdot \frac{{c}^{4}}{{b}^{6}} + \frac{81}{16} \cdot \frac{{c}^{4}}{{b}^{6}}\right)}{b}\right), a, \frac{-1}{2} \cdot \frac{c}{b}\right)} \]
      5. Applied rewrites98.1%

        \[\leadsto \color{blue}{\mathsf{fma}\left(\mathsf{fma}\left(\mathsf{fma}\left(-0.16666666666666666 \cdot a, \frac{{c}^{4}}{{b}^{6}} \cdot \frac{6.328125}{b}, \frac{{c}^{3} \cdot -0.5625}{{b}^{5}}\right), a, \frac{\left(c \cdot c\right) \cdot -0.375}{{b}^{3}}\right), a, \frac{c}{b} \cdot -0.5\right)} \]
      6. Taylor expanded in b around 0

        \[\leadsto \mathsf{fma}\left(\frac{\frac{-135}{128} \cdot \left({a}^{2} \cdot {c}^{4}\right) + {b}^{2} \cdot \left(\frac{-9}{16} \cdot \left(a \cdot {c}^{3}\right) + \frac{-3}{8} \cdot \left({b}^{2} \cdot {c}^{2}\right)\right)}{{b}^{7}}, a, \frac{c}{b} \cdot \frac{-1}{2}\right) \]
      7. Step-by-step derivation
        1. Applied rewrites98.1%

          \[\leadsto \mathsf{fma}\left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\left(b \cdot \left(c \cdot c\right)\right) \cdot b, -0.375, \left({c}^{3} \cdot a\right) \cdot -0.5625\right) \cdot b, b, \left(-1.0546875 \cdot {c}^{4}\right) \cdot \left(a \cdot a\right)\right)}{{b}^{7}}, a, \frac{c}{b} \cdot -0.5\right) \]
        2. Taylor expanded in c around 0

          \[\leadsto \mathsf{fma}\left(\frac{\mathsf{fma}\left(\left({c}^{2} \cdot \left(\frac{-9}{16} \cdot \left(a \cdot c\right) + \frac{-3}{8} \cdot {b}^{2}\right)\right) \cdot b, b, \left(\frac{-135}{128} \cdot {c}^{4}\right) \cdot \left(a \cdot a\right)\right)}{{b}^{7}}, a, \frac{c}{b} \cdot \frac{-1}{2}\right) \]
        3. Step-by-step derivation
          1. Applied rewrites98.1%

            \[\leadsto \mathsf{fma}\left(\frac{\mathsf{fma}\left(\left(\left(c \cdot c\right) \cdot \mathsf{fma}\left(-0.5625, a \cdot c, -0.375 \cdot \left(b \cdot b\right)\right)\right) \cdot b, b, \left(-1.0546875 \cdot {c}^{4}\right) \cdot \left(a \cdot a\right)\right)}{{b}^{7}}, a, \frac{c}{b} \cdot -0.5\right) \]
          2. Applied rewrites97.8%

            \[\leadsto \mathsf{fma}\left(\frac{-0.5}{b}, \color{blue}{c}, \left({b}^{-7} \cdot \mathsf{fma}\left(\left(\mathsf{fma}\left(c \cdot a, -0.5625, \left(b \cdot b\right) \cdot -0.375\right) \cdot c\right) \cdot c, b \cdot b, \left(\left(a \cdot a\right) \cdot -1.0546875\right) \cdot {c}^{4}\right)\right) \cdot a\right) \]
          3. Final simplification97.8%

            \[\leadsto \mathsf{fma}\left(\frac{-0.5}{b}, c, \left(\mathsf{fma}\left(\left(\mathsf{fma}\left(c \cdot a, -0.5625, \left(b \cdot b\right) \cdot -0.375\right) \cdot c\right) \cdot c, b \cdot b, {c}^{4} \cdot \left(-1.0546875 \cdot \left(a \cdot a\right)\right)\right) \cdot {b}^{-7}\right) \cdot a\right) \]
          4. Add Preprocessing

          Alternative 3: 97.0% accurate, 0.2× speedup?

          \[\begin{array}{l} \\ \mathsf{fma}\left(\left(c \cdot c\right) \cdot \mathsf{fma}\left(-0.5625 \cdot a, \frac{c}{{b}^{5}}, \frac{-0.375}{{b}^{3}}\right), a, -0.5 \cdot \frac{c}{b}\right) \end{array} \]
          (FPCore (a b c)
           :precision binary64
           (fma
            (* (* c c) (fma (* -0.5625 a) (/ c (pow b 5.0)) (/ -0.375 (pow b 3.0))))
            a
            (* -0.5 (/ c b))))
          double code(double a, double b, double c) {
          	return fma(((c * c) * fma((-0.5625 * a), (c / pow(b, 5.0)), (-0.375 / pow(b, 3.0)))), a, (-0.5 * (c / b)));
          }
          
          function code(a, b, c)
          	return fma(Float64(Float64(c * c) * fma(Float64(-0.5625 * a), Float64(c / (b ^ 5.0)), Float64(-0.375 / (b ^ 3.0)))), a, Float64(-0.5 * Float64(c / b)))
          end
          
          code[a_, b_, c_] := N[(N[(N[(c * c), $MachinePrecision] * N[(N[(-0.5625 * a), $MachinePrecision] * N[(c / N[Power[b, 5.0], $MachinePrecision]), $MachinePrecision] + N[(-0.375 / N[Power[b, 3.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] * a + N[(-0.5 * N[(c / b), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
          
          \begin{array}{l}
          
          \\
          \mathsf{fma}\left(\left(c \cdot c\right) \cdot \mathsf{fma}\left(-0.5625 \cdot a, \frac{c}{{b}^{5}}, \frac{-0.375}{{b}^{3}}\right), a, -0.5 \cdot \frac{c}{b}\right)
          \end{array}
          
          Derivation
          1. Initial program 18.0%

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

            \[\leadsto \color{blue}{\frac{-1}{2} \cdot \frac{c}{b} + a \cdot \left(\frac{-3}{8} \cdot \frac{{c}^{2}}{{b}^{3}} + a \cdot \left(\frac{-9}{16} \cdot \frac{{c}^{3}}{{b}^{5}} + \frac{-1}{6} \cdot \frac{a \cdot \left(\frac{81}{64} \cdot \frac{{c}^{4}}{{b}^{6}} + \frac{81}{16} \cdot \frac{{c}^{4}}{{b}^{6}}\right)}{b}\right)\right)} \]
          4. Step-by-step derivation
            1. +-commutativeN/A

              \[\leadsto \color{blue}{a \cdot \left(\frac{-3}{8} \cdot \frac{{c}^{2}}{{b}^{3}} + a \cdot \left(\frac{-9}{16} \cdot \frac{{c}^{3}}{{b}^{5}} + \frac{-1}{6} \cdot \frac{a \cdot \left(\frac{81}{64} \cdot \frac{{c}^{4}}{{b}^{6}} + \frac{81}{16} \cdot \frac{{c}^{4}}{{b}^{6}}\right)}{b}\right)\right) + \frac{-1}{2} \cdot \frac{c}{b}} \]
            2. *-commutativeN/A

              \[\leadsto \color{blue}{\left(\frac{-3}{8} \cdot \frac{{c}^{2}}{{b}^{3}} + a \cdot \left(\frac{-9}{16} \cdot \frac{{c}^{3}}{{b}^{5}} + \frac{-1}{6} \cdot \frac{a \cdot \left(\frac{81}{64} \cdot \frac{{c}^{4}}{{b}^{6}} + \frac{81}{16} \cdot \frac{{c}^{4}}{{b}^{6}}\right)}{b}\right)\right) \cdot a} + \frac{-1}{2} \cdot \frac{c}{b} \]
            3. lower-fma.f64N/A

              \[\leadsto \color{blue}{\mathsf{fma}\left(\frac{-3}{8} \cdot \frac{{c}^{2}}{{b}^{3}} + a \cdot \left(\frac{-9}{16} \cdot \frac{{c}^{3}}{{b}^{5}} + \frac{-1}{6} \cdot \frac{a \cdot \left(\frac{81}{64} \cdot \frac{{c}^{4}}{{b}^{6}} + \frac{81}{16} \cdot \frac{{c}^{4}}{{b}^{6}}\right)}{b}\right), a, \frac{-1}{2} \cdot \frac{c}{b}\right)} \]
          5. Applied rewrites98.1%

            \[\leadsto \color{blue}{\mathsf{fma}\left(\mathsf{fma}\left(\mathsf{fma}\left(-0.16666666666666666 \cdot a, \frac{{c}^{4}}{{b}^{6}} \cdot \frac{6.328125}{b}, \frac{{c}^{3} \cdot -0.5625}{{b}^{5}}\right), a, \frac{\left(c \cdot c\right) \cdot -0.375}{{b}^{3}}\right), a, \frac{c}{b} \cdot -0.5\right)} \]
          6. Taylor expanded in c around 0

            \[\leadsto \mathsf{fma}\left({c}^{2} \cdot \left(\frac{-9}{16} \cdot \frac{a \cdot c}{{b}^{5}} - \frac{3}{8} \cdot \frac{1}{{b}^{3}}\right), a, \frac{c}{b} \cdot \frac{-1}{2}\right) \]
          7. Step-by-step derivation
            1. Applied rewrites97.4%

              \[\leadsto \mathsf{fma}\left(\mathsf{fma}\left(-0.5625 \cdot a, \frac{c}{{b}^{5}}, \frac{-0.375}{{b}^{3}}\right) \cdot \left(c \cdot c\right), a, \frac{c}{b} \cdot -0.5\right) \]
            2. Final simplification97.4%

              \[\leadsto \mathsf{fma}\left(\left(c \cdot c\right) \cdot \mathsf{fma}\left(-0.5625 \cdot a, \frac{c}{{b}^{5}}, \frac{-0.375}{{b}^{3}}\right), a, -0.5 \cdot \frac{c}{b}\right) \]
            3. Add Preprocessing

            Alternative 4: 97.0% accurate, 0.2× speedup?

            \[\begin{array}{l} \\ \frac{\mathsf{fma}\left(\frac{\left(c \cdot c\right) \cdot -0.375}{b}, \frac{a}{b}, \mathsf{fma}\left(\frac{\frac{\left({c}^{3} \cdot a\right) \cdot a}{b \cdot b}}{b \cdot b}, -0.5625, -0.5 \cdot c\right)\right)}{b} \end{array} \]
            (FPCore (a b c)
             :precision binary64
             (/
              (fma
               (/ (* (* c c) -0.375) b)
               (/ a b)
               (fma (/ (/ (* (* (pow c 3.0) a) a) (* b b)) (* b b)) -0.5625 (* -0.5 c)))
              b))
            double code(double a, double b, double c) {
            	return fma((((c * c) * -0.375) / b), (a / b), fma(((((pow(c, 3.0) * a) * a) / (b * b)) / (b * b)), -0.5625, (-0.5 * c))) / b;
            }
            
            function code(a, b, c)
            	return Float64(fma(Float64(Float64(Float64(c * c) * -0.375) / b), Float64(a / b), fma(Float64(Float64(Float64(Float64((c ^ 3.0) * a) * a) / Float64(b * b)) / Float64(b * b)), -0.5625, Float64(-0.5 * c))) / b)
            end
            
            code[a_, b_, c_] := N[(N[(N[(N[(N[(c * c), $MachinePrecision] * -0.375), $MachinePrecision] / b), $MachinePrecision] * N[(a / b), $MachinePrecision] + N[(N[(N[(N[(N[(N[Power[c, 3.0], $MachinePrecision] * a), $MachinePrecision] * a), $MachinePrecision] / N[(b * b), $MachinePrecision]), $MachinePrecision] / N[(b * b), $MachinePrecision]), $MachinePrecision] * -0.5625 + N[(-0.5 * c), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / b), $MachinePrecision]
            
            \begin{array}{l}
            
            \\
            \frac{\mathsf{fma}\left(\frac{\left(c \cdot c\right) \cdot -0.375}{b}, \frac{a}{b}, \mathsf{fma}\left(\frac{\frac{\left({c}^{3} \cdot a\right) \cdot a}{b \cdot b}}{b \cdot b}, -0.5625, -0.5 \cdot c\right)\right)}{b}
            \end{array}
            
            Derivation
            1. Initial program 18.0%

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

              \[\leadsto \color{blue}{\frac{\frac{-9}{16} \cdot \frac{{a}^{2} \cdot {c}^{3}}{{b}^{4}} + \left(\frac{-1}{2} \cdot c + \frac{-3}{8} \cdot \frac{a \cdot {c}^{2}}{{b}^{2}}\right)}{b}} \]
            4. Step-by-step derivation
              1. lower-/.f64N/A

                \[\leadsto \color{blue}{\frac{\frac{-9}{16} \cdot \frac{{a}^{2} \cdot {c}^{3}}{{b}^{4}} + \left(\frac{-1}{2} \cdot c + \frac{-3}{8} \cdot \frac{a \cdot {c}^{2}}{{b}^{2}}\right)}{b}} \]
            5. Applied rewrites97.4%

              \[\leadsto \color{blue}{\frac{\mathsf{fma}\left(\frac{\left(c \cdot c\right) \cdot -0.375}{b}, \frac{a}{b}, \mathsf{fma}\left(\frac{\left({c}^{3} \cdot a\right) \cdot a}{{b}^{4}}, -0.5625, -0.5 \cdot c\right)\right)}{b}} \]
            6. Step-by-step derivation
              1. Applied rewrites97.4%

                \[\leadsto \frac{\mathsf{fma}\left(\frac{\left(c \cdot c\right) \cdot -0.375}{b}, \frac{a}{b}, \mathsf{fma}\left(\frac{\frac{\left({c}^{3} \cdot a\right) \cdot a}{b \cdot b}}{b \cdot b}, -0.5625, -0.5 \cdot c\right)\right)}{b} \]
              2. Add Preprocessing

              Alternative 5: 97.0% accurate, 0.3× speedup?

              \[\begin{array}{l} \\ \frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{-0.375}{b}, \frac{a}{b}, \frac{c}{{b}^{4}} \cdot \left(\left(a \cdot a\right) \cdot -0.5625\right)\right), c, -0.5\right) \cdot c}{b} \end{array} \]
              (FPCore (a b c)
               :precision binary64
               (/
                (*
                 (fma
                  (fma (/ -0.375 b) (/ a b) (* (/ c (pow b 4.0)) (* (* a a) -0.5625)))
                  c
                  -0.5)
                 c)
                b))
              double code(double a, double b, double c) {
              	return (fma(fma((-0.375 / b), (a / b), ((c / pow(b, 4.0)) * ((a * a) * -0.5625))), c, -0.5) * c) / b;
              }
              
              function code(a, b, c)
              	return Float64(Float64(fma(fma(Float64(-0.375 / b), Float64(a / b), Float64(Float64(c / (b ^ 4.0)) * Float64(Float64(a * a) * -0.5625))), c, -0.5) * c) / b)
              end
              
              code[a_, b_, c_] := N[(N[(N[(N[(N[(-0.375 / b), $MachinePrecision] * N[(a / b), $MachinePrecision] + N[(N[(c / N[Power[b, 4.0], $MachinePrecision]), $MachinePrecision] * N[(N[(a * a), $MachinePrecision] * -0.5625), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] * c + -0.5), $MachinePrecision] * c), $MachinePrecision] / b), $MachinePrecision]
              
              \begin{array}{l}
              
              \\
              \frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{-0.375}{b}, \frac{a}{b}, \frac{c}{{b}^{4}} \cdot \left(\left(a \cdot a\right) \cdot -0.5625\right)\right), c, -0.5\right) \cdot c}{b}
              \end{array}
              
              Derivation
              1. Initial program 18.0%

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

                \[\leadsto \color{blue}{\frac{\frac{-9}{16} \cdot \frac{{a}^{2} \cdot {c}^{3}}{{b}^{4}} + \left(\frac{-1}{2} \cdot c + \frac{-3}{8} \cdot \frac{a \cdot {c}^{2}}{{b}^{2}}\right)}{b}} \]
              4. Step-by-step derivation
                1. lower-/.f64N/A

                  \[\leadsto \color{blue}{\frac{\frac{-9}{16} \cdot \frac{{a}^{2} \cdot {c}^{3}}{{b}^{4}} + \left(\frac{-1}{2} \cdot c + \frac{-3}{8} \cdot \frac{a \cdot {c}^{2}}{{b}^{2}}\right)}{b}} \]
              5. Applied rewrites97.4%

                \[\leadsto \color{blue}{\frac{\mathsf{fma}\left(\frac{\left(c \cdot c\right) \cdot -0.375}{b}, \frac{a}{b}, \mathsf{fma}\left(\frac{\left({c}^{3} \cdot a\right) \cdot a}{{b}^{4}}, -0.5625, -0.5 \cdot c\right)\right)}{b}} \]
              6. Taylor expanded in c around 0

                \[\leadsto \frac{c \cdot \left(c \cdot \left(\frac{-9}{16} \cdot \frac{{a}^{2} \cdot c}{{b}^{4}} + \frac{-3}{8} \cdot \frac{a}{{b}^{2}}\right) - \frac{1}{2}\right)}{b} \]
              7. Step-by-step derivation
                1. Applied rewrites97.4%

                  \[\leadsto \frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{-0.375}{b}, \frac{a}{b}, \left(-0.5625 \cdot \left(a \cdot a\right)\right) \cdot \frac{c}{{b}^{4}}\right), c, -0.5\right) \cdot c}{b} \]
                2. Final simplification97.4%

                  \[\leadsto \frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{-0.375}{b}, \frac{a}{b}, \frac{c}{{b}^{4}} \cdot \left(\left(a \cdot a\right) \cdot -0.5625\right)\right), c, -0.5\right) \cdot c}{b} \]
                3. Add Preprocessing

                Alternative 6: 95.5% accurate, 0.3× speedup?

                \[\begin{array}{l} \\ \mathsf{fma}\left(-0.375 \cdot a, \frac{c}{{b}^{3}} \cdot c, -0.5 \cdot \frac{c}{b}\right) \end{array} \]
                (FPCore (a b c)
                 :precision binary64
                 (fma (* -0.375 a) (* (/ c (pow b 3.0)) c) (* -0.5 (/ c b))))
                double code(double a, double b, double c) {
                	return fma((-0.375 * a), ((c / pow(b, 3.0)) * c), (-0.5 * (c / b)));
                }
                
                function code(a, b, c)
                	return fma(Float64(-0.375 * a), Float64(Float64(c / (b ^ 3.0)) * c), Float64(-0.5 * Float64(c / b)))
                end
                
                code[a_, b_, c_] := N[(N[(-0.375 * a), $MachinePrecision] * N[(N[(c / N[Power[b, 3.0], $MachinePrecision]), $MachinePrecision] * c), $MachinePrecision] + N[(-0.5 * N[(c / b), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
                
                \begin{array}{l}
                
                \\
                \mathsf{fma}\left(-0.375 \cdot a, \frac{c}{{b}^{3}} \cdot c, -0.5 \cdot \frac{c}{b}\right)
                \end{array}
                
                Derivation
                1. Initial program 18.0%

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

                  \[\leadsto \color{blue}{\frac{-1}{2} \cdot \frac{c}{b} + \frac{-3}{8} \cdot \frac{a \cdot {c}^{2}}{{b}^{3}}} \]
                4. Step-by-step derivation
                  1. +-commutativeN/A

                    \[\leadsto \color{blue}{\frac{-3}{8} \cdot \frac{a \cdot {c}^{2}}{{b}^{3}} + \frac{-1}{2} \cdot \frac{c}{b}} \]
                  2. associate-/l*N/A

                    \[\leadsto \frac{-3}{8} \cdot \color{blue}{\left(a \cdot \frac{{c}^{2}}{{b}^{3}}\right)} + \frac{-1}{2} \cdot \frac{c}{b} \]
                  3. associate-*r*N/A

                    \[\leadsto \color{blue}{\left(\frac{-3}{8} \cdot a\right) \cdot \frac{{c}^{2}}{{b}^{3}}} + \frac{-1}{2} \cdot \frac{c}{b} \]
                  4. lower-fma.f64N/A

                    \[\leadsto \color{blue}{\mathsf{fma}\left(\frac{-3}{8} \cdot a, \frac{{c}^{2}}{{b}^{3}}, \frac{-1}{2} \cdot \frac{c}{b}\right)} \]
                  5. lower-*.f64N/A

                    \[\leadsto \mathsf{fma}\left(\color{blue}{\frac{-3}{8} \cdot a}, \frac{{c}^{2}}{{b}^{3}}, \frac{-1}{2} \cdot \frac{c}{b}\right) \]
                  6. unpow2N/A

                    \[\leadsto \mathsf{fma}\left(\frac{-3}{8} \cdot a, \frac{\color{blue}{c \cdot c}}{{b}^{3}}, \frac{-1}{2} \cdot \frac{c}{b}\right) \]
                  7. associate-/l*N/A

                    \[\leadsto \mathsf{fma}\left(\frac{-3}{8} \cdot a, \color{blue}{c \cdot \frac{c}{{b}^{3}}}, \frac{-1}{2} \cdot \frac{c}{b}\right) \]
                  8. lower-*.f64N/A

                    \[\leadsto \mathsf{fma}\left(\frac{-3}{8} \cdot a, \color{blue}{c \cdot \frac{c}{{b}^{3}}}, \frac{-1}{2} \cdot \frac{c}{b}\right) \]
                  9. lower-/.f64N/A

                    \[\leadsto \mathsf{fma}\left(\frac{-3}{8} \cdot a, c \cdot \color{blue}{\frac{c}{{b}^{3}}}, \frac{-1}{2} \cdot \frac{c}{b}\right) \]
                  10. lower-pow.f64N/A

                    \[\leadsto \mathsf{fma}\left(\frac{-3}{8} \cdot a, c \cdot \frac{c}{\color{blue}{{b}^{3}}}, \frac{-1}{2} \cdot \frac{c}{b}\right) \]
                  11. *-commutativeN/A

                    \[\leadsto \mathsf{fma}\left(\frac{-3}{8} \cdot a, c \cdot \frac{c}{{b}^{3}}, \color{blue}{\frac{c}{b} \cdot \frac{-1}{2}}\right) \]
                  12. lower-*.f64N/A

                    \[\leadsto \mathsf{fma}\left(\frac{-3}{8} \cdot a, c \cdot \frac{c}{{b}^{3}}, \color{blue}{\frac{c}{b} \cdot \frac{-1}{2}}\right) \]
                  13. lower-/.f6495.9

                    \[\leadsto \mathsf{fma}\left(-0.375 \cdot a, c \cdot \frac{c}{{b}^{3}}, \color{blue}{\frac{c}{b}} \cdot -0.5\right) \]
                5. Applied rewrites95.9%

                  \[\leadsto \color{blue}{\mathsf{fma}\left(-0.375 \cdot a, c \cdot \frac{c}{{b}^{3}}, \frac{c}{b} \cdot -0.5\right)} \]
                6. Final simplification95.9%

                  \[\leadsto \mathsf{fma}\left(-0.375 \cdot a, \frac{c}{{b}^{3}} \cdot c, -0.5 \cdot \frac{c}{b}\right) \]
                7. Add Preprocessing

                Alternative 7: 95.4% accurate, 1.0× speedup?

                \[\begin{array}{l} \\ \frac{\mathsf{fma}\left(\frac{-0.375}{b}, \frac{c}{b} \cdot a, -0.5\right) \cdot c}{b} \end{array} \]
                (FPCore (a b c)
                 :precision binary64
                 (/ (* (fma (/ -0.375 b) (* (/ c b) a) -0.5) c) b))
                double code(double a, double b, double c) {
                	return (fma((-0.375 / b), ((c / b) * a), -0.5) * c) / b;
                }
                
                function code(a, b, c)
                	return Float64(Float64(fma(Float64(-0.375 / b), Float64(Float64(c / b) * a), -0.5) * c) / b)
                end
                
                code[a_, b_, c_] := N[(N[(N[(N[(-0.375 / b), $MachinePrecision] * N[(N[(c / b), $MachinePrecision] * a), $MachinePrecision] + -0.5), $MachinePrecision] * c), $MachinePrecision] / b), $MachinePrecision]
                
                \begin{array}{l}
                
                \\
                \frac{\mathsf{fma}\left(\frac{-0.375}{b}, \frac{c}{b} \cdot a, -0.5\right) \cdot c}{b}
                \end{array}
                
                Derivation
                1. Initial program 18.0%

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

                  \[\leadsto \color{blue}{\frac{\frac{-9}{16} \cdot \frac{{a}^{2} \cdot {c}^{3}}{{b}^{4}} + \left(\frac{-1}{2} \cdot c + \frac{-3}{8} \cdot \frac{a \cdot {c}^{2}}{{b}^{2}}\right)}{b}} \]
                4. Step-by-step derivation
                  1. lower-/.f64N/A

                    \[\leadsto \color{blue}{\frac{\frac{-9}{16} \cdot \frac{{a}^{2} \cdot {c}^{3}}{{b}^{4}} + \left(\frac{-1}{2} \cdot c + \frac{-3}{8} \cdot \frac{a \cdot {c}^{2}}{{b}^{2}}\right)}{b}} \]
                5. Applied rewrites97.4%

                  \[\leadsto \color{blue}{\frac{\mathsf{fma}\left(\frac{\left(c \cdot c\right) \cdot -0.375}{b}, \frac{a}{b}, \mathsf{fma}\left(\frac{\left({c}^{3} \cdot a\right) \cdot a}{{b}^{4}}, -0.5625, -0.5 \cdot c\right)\right)}{b}} \]
                6. Taylor expanded in c around 0

                  \[\leadsto \frac{c \cdot \left(\frac{-3}{8} \cdot \frac{a \cdot c}{{b}^{2}} - \frac{1}{2}\right)}{b} \]
                7. Step-by-step derivation
                  1. Applied rewrites95.8%

                    \[\leadsto \frac{\mathsf{fma}\left(\frac{-0.375}{b}, a \cdot \frac{c}{b}, -0.5\right) \cdot c}{b} \]
                  2. Final simplification95.8%

                    \[\leadsto \frac{\mathsf{fma}\left(\frac{-0.375}{b}, \frac{c}{b} \cdot a, -0.5\right) \cdot c}{b} \]
                  3. Add Preprocessing

                  Alternative 8: 95.5% accurate, 1.0× speedup?

                  \[\begin{array}{l} \\ \frac{\mathsf{fma}\left(-0.375, \frac{\left(c \cdot c\right) \cdot a}{b \cdot b}, -0.5 \cdot c\right)}{b} \end{array} \]
                  (FPCore (a b c)
                   :precision binary64
                   (/ (fma -0.375 (/ (* (* c c) a) (* b b)) (* -0.5 c)) b))
                  double code(double a, double b, double c) {
                  	return fma(-0.375, (((c * c) * a) / (b * b)), (-0.5 * c)) / b;
                  }
                  
                  function code(a, b, c)
                  	return Float64(fma(-0.375, Float64(Float64(Float64(c * c) * a) / Float64(b * b)), Float64(-0.5 * c)) / b)
                  end
                  
                  code[a_, b_, c_] := N[(N[(-0.375 * N[(N[(N[(c * c), $MachinePrecision] * a), $MachinePrecision] / N[(b * b), $MachinePrecision]), $MachinePrecision] + N[(-0.5 * c), $MachinePrecision]), $MachinePrecision] / b), $MachinePrecision]
                  
                  \begin{array}{l}
                  
                  \\
                  \frac{\mathsf{fma}\left(-0.375, \frac{\left(c \cdot c\right) \cdot a}{b \cdot b}, -0.5 \cdot c\right)}{b}
                  \end{array}
                  
                  Derivation
                  1. Initial program 18.0%

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

                    \[\leadsto \color{blue}{\frac{-1}{2} \cdot \frac{c}{b} + a \cdot \left(\frac{-3}{8} \cdot \frac{{c}^{2}}{{b}^{3}} + a \cdot \left(\frac{-9}{16} \cdot \frac{{c}^{3}}{{b}^{5}} + \frac{-1}{6} \cdot \frac{a \cdot \left(\frac{81}{64} \cdot \frac{{c}^{4}}{{b}^{6}} + \frac{81}{16} \cdot \frac{{c}^{4}}{{b}^{6}}\right)}{b}\right)\right)} \]
                  4. Step-by-step derivation
                    1. +-commutativeN/A

                      \[\leadsto \color{blue}{a \cdot \left(\frac{-3}{8} \cdot \frac{{c}^{2}}{{b}^{3}} + a \cdot \left(\frac{-9}{16} \cdot \frac{{c}^{3}}{{b}^{5}} + \frac{-1}{6} \cdot \frac{a \cdot \left(\frac{81}{64} \cdot \frac{{c}^{4}}{{b}^{6}} + \frac{81}{16} \cdot \frac{{c}^{4}}{{b}^{6}}\right)}{b}\right)\right) + \frac{-1}{2} \cdot \frac{c}{b}} \]
                    2. *-commutativeN/A

                      \[\leadsto \color{blue}{\left(\frac{-3}{8} \cdot \frac{{c}^{2}}{{b}^{3}} + a \cdot \left(\frac{-9}{16} \cdot \frac{{c}^{3}}{{b}^{5}} + \frac{-1}{6} \cdot \frac{a \cdot \left(\frac{81}{64} \cdot \frac{{c}^{4}}{{b}^{6}} + \frac{81}{16} \cdot \frac{{c}^{4}}{{b}^{6}}\right)}{b}\right)\right) \cdot a} + \frac{-1}{2} \cdot \frac{c}{b} \]
                    3. lower-fma.f64N/A

                      \[\leadsto \color{blue}{\mathsf{fma}\left(\frac{-3}{8} \cdot \frac{{c}^{2}}{{b}^{3}} + a \cdot \left(\frac{-9}{16} \cdot \frac{{c}^{3}}{{b}^{5}} + \frac{-1}{6} \cdot \frac{a \cdot \left(\frac{81}{64} \cdot \frac{{c}^{4}}{{b}^{6}} + \frac{81}{16} \cdot \frac{{c}^{4}}{{b}^{6}}\right)}{b}\right), a, \frac{-1}{2} \cdot \frac{c}{b}\right)} \]
                  5. Applied rewrites98.1%

                    \[\leadsto \color{blue}{\mathsf{fma}\left(\mathsf{fma}\left(\mathsf{fma}\left(-0.16666666666666666 \cdot a, \frac{{c}^{4}}{{b}^{6}} \cdot \frac{6.328125}{b}, \frac{{c}^{3} \cdot -0.5625}{{b}^{5}}\right), a, \frac{\left(c \cdot c\right) \cdot -0.375}{{b}^{3}}\right), a, \frac{c}{b} \cdot -0.5\right)} \]
                  6. Taylor expanded in b around 0

                    \[\leadsto \mathsf{fma}\left(\frac{\frac{-135}{128} \cdot \left({a}^{2} \cdot {c}^{4}\right) + {b}^{2} \cdot \left(\frac{-9}{16} \cdot \left(a \cdot {c}^{3}\right) + \frac{-3}{8} \cdot \left({b}^{2} \cdot {c}^{2}\right)\right)}{{b}^{7}}, a, \frac{c}{b} \cdot \frac{-1}{2}\right) \]
                  7. Step-by-step derivation
                    1. Applied rewrites98.1%

                      \[\leadsto \mathsf{fma}\left(\frac{\mathsf{fma}\left(\mathsf{fma}\left(\left(b \cdot \left(c \cdot c\right)\right) \cdot b, -0.375, \left({c}^{3} \cdot a\right) \cdot -0.5625\right) \cdot b, b, \left(-1.0546875 \cdot {c}^{4}\right) \cdot \left(a \cdot a\right)\right)}{{b}^{7}}, a, \frac{c}{b} \cdot -0.5\right) \]
                    2. Taylor expanded in b around inf

                      \[\leadsto \color{blue}{\frac{\frac{-1}{2} \cdot c + \frac{-3}{8} \cdot \frac{a \cdot {c}^{2}}{{b}^{2}}}{b}} \]
                    3. Step-by-step derivation
                      1. lower-/.f64N/A

                        \[\leadsto \color{blue}{\frac{\frac{-1}{2} \cdot c + \frac{-3}{8} \cdot \frac{a \cdot {c}^{2}}{{b}^{2}}}{b}} \]
                      2. +-commutativeN/A

                        \[\leadsto \frac{\color{blue}{\frac{-3}{8} \cdot \frac{a \cdot {c}^{2}}{{b}^{2}} + \frac{-1}{2} \cdot c}}{b} \]
                      3. lower-fma.f64N/A

                        \[\leadsto \frac{\color{blue}{\mathsf{fma}\left(\frac{-3}{8}, \frac{a \cdot {c}^{2}}{{b}^{2}}, \frac{-1}{2} \cdot c\right)}}{b} \]
                      4. lower-/.f64N/A

                        \[\leadsto \frac{\mathsf{fma}\left(\frac{-3}{8}, \color{blue}{\frac{a \cdot {c}^{2}}{{b}^{2}}}, \frac{-1}{2} \cdot c\right)}{b} \]
                      5. lower-*.f64N/A

                        \[\leadsto \frac{\mathsf{fma}\left(\frac{-3}{8}, \frac{\color{blue}{a \cdot {c}^{2}}}{{b}^{2}}, \frac{-1}{2} \cdot c\right)}{b} \]
                      6. unpow2N/A

                        \[\leadsto \frac{\mathsf{fma}\left(\frac{-3}{8}, \frac{a \cdot \color{blue}{\left(c \cdot c\right)}}{{b}^{2}}, \frac{-1}{2} \cdot c\right)}{b} \]
                      7. lower-*.f64N/A

                        \[\leadsto \frac{\mathsf{fma}\left(\frac{-3}{8}, \frac{a \cdot \color{blue}{\left(c \cdot c\right)}}{{b}^{2}}, \frac{-1}{2} \cdot c\right)}{b} \]
                      8. unpow2N/A

                        \[\leadsto \frac{\mathsf{fma}\left(\frac{-3}{8}, \frac{a \cdot \left(c \cdot c\right)}{\color{blue}{b \cdot b}}, \frac{-1}{2} \cdot c\right)}{b} \]
                      9. lower-*.f64N/A

                        \[\leadsto \frac{\mathsf{fma}\left(\frac{-3}{8}, \frac{a \cdot \left(c \cdot c\right)}{\color{blue}{b \cdot b}}, \frac{-1}{2} \cdot c\right)}{b} \]
                      10. lower-*.f6495.8

                        \[\leadsto \frac{\mathsf{fma}\left(-0.375, \frac{a \cdot \left(c \cdot c\right)}{b \cdot b}, \color{blue}{-0.5 \cdot c}\right)}{b} \]
                    4. Applied rewrites95.8%

                      \[\leadsto \color{blue}{\frac{\mathsf{fma}\left(-0.375, \frac{a \cdot \left(c \cdot c\right)}{b \cdot b}, -0.5 \cdot c\right)}{b}} \]
                    5. Final simplification95.8%

                      \[\leadsto \frac{\mathsf{fma}\left(-0.375, \frac{\left(c \cdot c\right) \cdot a}{b \cdot b}, -0.5 \cdot c\right)}{b} \]
                    6. Add Preprocessing

                    Alternative 9: 90.6% accurate, 2.9× speedup?

                    \[\begin{array}{l} \\ -0.5 \cdot \frac{c}{b} \end{array} \]
                    (FPCore (a b c) :precision binary64 (* -0.5 (/ c b)))
                    double code(double a, double b, double c) {
                    	return -0.5 * (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 = (-0.5d0) * (c / b)
                    end function
                    
                    public static double code(double a, double b, double c) {
                    	return -0.5 * (c / b);
                    }
                    
                    def code(a, b, c):
                    	return -0.5 * (c / b)
                    
                    function code(a, b, c)
                    	return Float64(-0.5 * Float64(c / b))
                    end
                    
                    function tmp = code(a, b, c)
                    	tmp = -0.5 * (c / b);
                    end
                    
                    code[a_, b_, c_] := N[(-0.5 * N[(c / b), $MachinePrecision]), $MachinePrecision]
                    
                    \begin{array}{l}
                    
                    \\
                    -0.5 \cdot \frac{c}{b}
                    \end{array}
                    
                    Derivation
                    1. Initial program 18.0%

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

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

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

                        \[\leadsto \color{blue}{\frac{c}{b} \cdot \frac{-1}{2}} \]
                      3. lower-/.f6490.7

                        \[\leadsto \color{blue}{\frac{c}{b}} \cdot -0.5 \]
                    5. Applied rewrites90.7%

                      \[\leadsto \color{blue}{\frac{c}{b} \cdot -0.5} \]
                    6. Final simplification90.7%

                      \[\leadsto -0.5 \cdot \frac{c}{b} \]
                    7. Add Preprocessing

                    Alternative 10: 90.3% accurate, 2.9× speedup?

                    \[\begin{array}{l} \\ \frac{-0.5}{b} \cdot c \end{array} \]
                    (FPCore (a b c) :precision binary64 (* (/ -0.5 b) c))
                    double code(double a, double b, double c) {
                    	return (-0.5 / b) * c;
                    }
                    
                    real(8) function code(a, b, c)
                        real(8), intent (in) :: a
                        real(8), intent (in) :: b
                        real(8), intent (in) :: c
                        code = ((-0.5d0) / b) * c
                    end function
                    
                    public static double code(double a, double b, double c) {
                    	return (-0.5 / b) * c;
                    }
                    
                    def code(a, b, c):
                    	return (-0.5 / b) * c
                    
                    function code(a, b, c)
                    	return Float64(Float64(-0.5 / b) * c)
                    end
                    
                    function tmp = code(a, b, c)
                    	tmp = (-0.5 / b) * c;
                    end
                    
                    code[a_, b_, c_] := N[(N[(-0.5 / b), $MachinePrecision] * c), $MachinePrecision]
                    
                    \begin{array}{l}
                    
                    \\
                    \frac{-0.5}{b} \cdot c
                    \end{array}
                    
                    Derivation
                    1. Initial program 18.0%

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

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

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

                        \[\leadsto \color{blue}{\frac{c}{b} \cdot \frac{-1}{2}} \]
                      3. lower-/.f6490.7

                        \[\leadsto \color{blue}{\frac{c}{b}} \cdot -0.5 \]
                    5. Applied rewrites90.7%

                      \[\leadsto \color{blue}{\frac{c}{b} \cdot -0.5} \]
                    6. Step-by-step derivation
                      1. Applied rewrites90.4%

                        \[\leadsto c \cdot \color{blue}{\frac{-0.5}{b}} \]
                      2. Final simplification90.4%

                        \[\leadsto \frac{-0.5}{b} \cdot c \]
                      3. Add Preprocessing

                      Reproduce

                      ?
                      herbie shell --seed 2024244 
                      (FPCore (a b c)
                        :name "Cubic critical, wide range"
                        :precision binary64
                        :pre (and (and (and (< 4.930380657631324e-32 a) (< a 2.028240960365167e+31)) (and (< 4.930380657631324e-32 b) (< b 2.028240960365167e+31))) (and (< 4.930380657631324e-32 c) (< c 2.028240960365167e+31)))
                        (/ (+ (- b) (sqrt (- (* b b) (* (* 3.0 a) c)))) (* 3.0 a)))