Cubic critical, wide range

Percentage Accurate: 17.8% → 97.7%
Time: 11.3s
Alternatives: 9
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 9 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: 17.8% 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: 97.7% accurate, 0.2× speedup?

\[\begin{array}{l} \\ \mathsf{fma}\left(\frac{c}{b}, -0.5, \left(\mathsf{fma}\left(\left(\mathsf{fma}\left(b \cdot b, -0.375, \left(c \cdot a\right) \cdot -0.5625\right) \cdot c\right) \cdot c, b \cdot b, \left(a \cdot a\right) \cdot \left(-1.0546875 \cdot {c}^{4}\right)\right) \cdot {b}^{-7}\right) \cdot a\right) \end{array} \]
(FPCore (a b c)
 :precision binary64
 (fma
  (/ c b)
  -0.5
  (*
   (*
    (fma
     (* (* (fma (* b b) -0.375 (* (* c a) -0.5625)) c) c)
     (* b b)
     (* (* a a) (* -1.0546875 (pow c 4.0))))
    (pow b -7.0))
   a)))
double code(double a, double b, double c) {
	return fma((c / b), -0.5, ((fma(((fma((b * b), -0.375, ((c * a) * -0.5625)) * c) * c), (b * b), ((a * a) * (-1.0546875 * pow(c, 4.0)))) * pow(b, -7.0)) * a));
}
function code(a, b, c)
	return fma(Float64(c / b), -0.5, Float64(Float64(fma(Float64(Float64(fma(Float64(b * b), -0.375, Float64(Float64(c * a) * -0.5625)) * c) * c), Float64(b * b), Float64(Float64(a * a) * Float64(-1.0546875 * (c ^ 4.0)))) * (b ^ -7.0)) * a))
end
code[a_, b_, c_] := N[(N[(c / b), $MachinePrecision] * -0.5 + N[(N[(N[(N[(N[(N[(N[(b * b), $MachinePrecision] * -0.375 + N[(N[(c * a), $MachinePrecision] * -0.5625), $MachinePrecision]), $MachinePrecision] * c), $MachinePrecision] * c), $MachinePrecision] * N[(b * b), $MachinePrecision] + N[(N[(a * a), $MachinePrecision] * N[(-1.0546875 * N[Power[c, 4.0], $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(b \cdot b, -0.375, \left(c \cdot a\right) \cdot -0.5625\right) \cdot c\right) \cdot c, b \cdot b, \left(a \cdot a\right) \cdot \left(-1.0546875 \cdot {c}^{4}\right)\right) \cdot {b}^{-7}\right) \cdot a\right)
\end{array}
Derivation
  1. Initial program 18.9%

    \[\frac{\left(-b\right) + \sqrt{b \cdot b - \left(3 \cdot a\right) \cdot c}}{3 \cdot a} \]
  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 rewrites97.8%

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

    \[\leadsto \mathsf{fma}\left(\frac{\frac{-135}{128} \cdot \left({a}^{2} \cdot {c}^{4}\right) + {b}^{2} \cdot \left(\frac{-9}{16} \cdot \left(a \cdot {c}^{3}\right) + \frac{-3}{8} \cdot \left({b}^{2} \cdot {c}^{2}\right)\right)}{{b}^{7}}, a, \frac{-1}{2} \cdot \frac{c}{b}\right) \]
  7. Step-by-step derivation
    1. Applied rewrites97.8%

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

      \[\leadsto \mathsf{fma}\left(\frac{\mathsf{fma}\left(\frac{-135}{128} \cdot \left(a \cdot a\right), {c}^{4}, \left({c}^{2} \cdot \left(\frac{-9}{16} \cdot \left(a \cdot c\right) + \frac{-3}{8} \cdot {b}^{2}\right)\right) \cdot \left(b \cdot b\right)\right)}{{b}^{7}}, a, \frac{-1}{2} \cdot \frac{c}{b}\right) \]
    3. Step-by-step derivation
      1. Applied rewrites97.8%

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

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

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

      Alternative 2: 97.4% accurate, 0.2× speedup?

      \[\begin{array}{l} \\ \mathsf{fma}\left(c, \frac{-0.5}{b}, \left(\mathsf{fma}\left(\left(\mathsf{fma}\left(b \cdot b, -0.375, \left(c \cdot a\right) \cdot -0.5625\right) \cdot c\right) \cdot c, b \cdot b, \left(a \cdot a\right) \cdot \left(-1.0546875 \cdot {c}^{4}\right)\right) \cdot {b}^{-7}\right) \cdot a\right) \end{array} \]
      (FPCore (a b c)
       :precision binary64
       (fma
        c
        (/ -0.5 b)
        (*
         (*
          (fma
           (* (* (fma (* b b) -0.375 (* (* c a) -0.5625)) c) c)
           (* b b)
           (* (* a a) (* -1.0546875 (pow c 4.0))))
          (pow b -7.0))
         a)))
      double code(double a, double b, double c) {
      	return fma(c, (-0.5 / b), ((fma(((fma((b * b), -0.375, ((c * a) * -0.5625)) * c) * c), (b * b), ((a * a) * (-1.0546875 * pow(c, 4.0)))) * pow(b, -7.0)) * a));
      }
      
      function code(a, b, c)
      	return fma(c, Float64(-0.5 / b), Float64(Float64(fma(Float64(Float64(fma(Float64(b * b), -0.375, Float64(Float64(c * a) * -0.5625)) * c) * c), Float64(b * b), Float64(Float64(a * a) * Float64(-1.0546875 * (c ^ 4.0)))) * (b ^ -7.0)) * a))
      end
      
      code[a_, b_, c_] := N[(c * N[(-0.5 / b), $MachinePrecision] + N[(N[(N[(N[(N[(N[(N[(b * b), $MachinePrecision] * -0.375 + N[(N[(c * a), $MachinePrecision] * -0.5625), $MachinePrecision]), $MachinePrecision] * c), $MachinePrecision] * c), $MachinePrecision] * N[(b * b), $MachinePrecision] + N[(N[(a * a), $MachinePrecision] * N[(-1.0546875 * N[Power[c, 4.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] * N[Power[b, -7.0], $MachinePrecision]), $MachinePrecision] * a), $MachinePrecision]), $MachinePrecision]
      
      \begin{array}{l}
      
      \\
      \mathsf{fma}\left(c, \frac{-0.5}{b}, \left(\mathsf{fma}\left(\left(\mathsf{fma}\left(b \cdot b, -0.375, \left(c \cdot a\right) \cdot -0.5625\right) \cdot c\right) \cdot c, b \cdot b, \left(a \cdot a\right) \cdot \left(-1.0546875 \cdot {c}^{4}\right)\right) \cdot {b}^{-7}\right) \cdot a\right)
      \end{array}
      
      Derivation
      1. Initial program 18.9%

        \[\frac{\left(-b\right) + \sqrt{b \cdot b - \left(3 \cdot a\right) \cdot c}}{3 \cdot a} \]
      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 rewrites97.8%

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

        \[\leadsto \mathsf{fma}\left(\frac{\frac{-135}{128} \cdot \left({a}^{2} \cdot {c}^{4}\right) + {b}^{2} \cdot \left(\frac{-9}{16} \cdot \left(a \cdot {c}^{3}\right) + \frac{-3}{8} \cdot \left({b}^{2} \cdot {c}^{2}\right)\right)}{{b}^{7}}, a, \frac{-1}{2} \cdot \frac{c}{b}\right) \]
      7. Step-by-step derivation
        1. Applied rewrites97.8%

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

          \[\leadsto \mathsf{fma}\left(\frac{\mathsf{fma}\left(\frac{-135}{128} \cdot \left(a \cdot a\right), {c}^{4}, \left({c}^{2} \cdot \left(\frac{-9}{16} \cdot \left(a \cdot c\right) + \frac{-3}{8} \cdot {b}^{2}\right)\right) \cdot \left(b \cdot b\right)\right)}{{b}^{7}}, a, \frac{-1}{2} \cdot \frac{c}{b}\right) \]
        3. Step-by-step derivation
          1. Applied rewrites97.8%

            \[\leadsto \mathsf{fma}\left(\frac{\mathsf{fma}\left(-1.0546875 \cdot \left(a \cdot a\right), {c}^{4}, \left(\left(c \cdot c\right) \cdot \mathsf{fma}\left(-0.375, b \cdot b, -0.5625 \cdot \left(a \cdot c\right)\right)\right) \cdot \left(b \cdot b\right)\right)}{{b}^{7}}, a, -0.5 \cdot \frac{c}{b}\right) \]
          2. Applied rewrites97.5%

            \[\leadsto \mathsf{fma}\left(c, \color{blue}{\frac{-0.5}{b}}, \left({b}^{-7} \cdot \mathsf{fma}\left(\left(\mathsf{fma}\left(b \cdot b, -0.375, \left(c \cdot a\right) \cdot -0.5625\right) \cdot c\right) \cdot c, b \cdot b, \left({c}^{4} \cdot -1.0546875\right) \cdot \left(a \cdot a\right)\right)\right) \cdot a\right) \]
          3. Final simplification97.5%

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

          Alternative 3: 96.8% accurate, 0.2× speedup?

          \[\begin{array}{l} \\ \frac{\mathsf{fma}\left(\frac{-0.375 \cdot a}{b}, \frac{c \cdot c}{b}, \mathsf{fma}\left(\frac{\left({c}^{3} \cdot a\right) \cdot a}{{b}^{4}}, -0.5625, -0.5 \cdot c\right)\right)}{b} \end{array} \]
          (FPCore (a b c)
           :precision binary64
           (/
            (fma
             (/ (* -0.375 a) b)
             (/ (* c c) b)
             (fma (/ (* (* (pow c 3.0) a) a) (pow b 4.0)) -0.5625 (* -0.5 c)))
            b))
          double code(double a, double b, double c) {
          	return fma(((-0.375 * a) / b), ((c * c) / b), fma((((pow(c, 3.0) * a) * a) / pow(b, 4.0)), -0.5625, (-0.5 * c))) / b;
          }
          
          function code(a, b, c)
          	return Float64(fma(Float64(Float64(-0.375 * a) / b), Float64(Float64(c * c) / b), fma(Float64(Float64(Float64((c ^ 3.0) * a) * a) / (b ^ 4.0)), -0.5625, Float64(-0.5 * c))) / b)
          end
          
          code[a_, b_, c_] := N[(N[(N[(N[(-0.375 * a), $MachinePrecision] / b), $MachinePrecision] * N[(N[(c * c), $MachinePrecision] / b), $MachinePrecision] + N[(N[(N[(N[(N[Power[c, 3.0], $MachinePrecision] * a), $MachinePrecision] * a), $MachinePrecision] / N[Power[b, 4.0], $MachinePrecision]), $MachinePrecision] * -0.5625 + N[(-0.5 * c), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] / b), $MachinePrecision]
          
          \begin{array}{l}
          
          \\
          \frac{\mathsf{fma}\left(\frac{-0.375 \cdot a}{b}, \frac{c \cdot c}{b}, \mathsf{fma}\left(\frac{\left({c}^{3} \cdot a\right) \cdot a}{{b}^{4}}, -0.5625, -0.5 \cdot c\right)\right)}{b}
          \end{array}
          
          Derivation
          1. Initial program 18.9%

            \[\frac{\left(-b\right) + \sqrt{b \cdot b - \left(3 \cdot a\right) \cdot c}}{3 \cdot a} \]
          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 rewrites96.5%

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

          Alternative 4: 96.6% accurate, 0.3× speedup?

          \[\begin{array}{l} \\ \frac{0.3333333333333333}{\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{0.375 \cdot \left(a \cdot a\right)}{{b}^{3}}, c, 0.5 \cdot \frac{a}{b}\right), c, -0.6666666666666666 \cdot b\right)}{c}} \end{array} \]
          (FPCore (a b c)
           :precision binary64
           (/
            0.3333333333333333
            (/
             (fma
              (fma (/ (* 0.375 (* a a)) (pow b 3.0)) c (* 0.5 (/ a b)))
              c
              (* -0.6666666666666666 b))
             c)))
          double code(double a, double b, double c) {
          	return 0.3333333333333333 / (fma(fma(((0.375 * (a * a)) / pow(b, 3.0)), c, (0.5 * (a / b))), c, (-0.6666666666666666 * b)) / c);
          }
          
          function code(a, b, c)
          	return Float64(0.3333333333333333 / Float64(fma(fma(Float64(Float64(0.375 * Float64(a * a)) / (b ^ 3.0)), c, Float64(0.5 * Float64(a / b))), c, Float64(-0.6666666666666666 * b)) / c))
          end
          
          code[a_, b_, c_] := N[(0.3333333333333333 / N[(N[(N[(N[(N[(0.375 * N[(a * a), $MachinePrecision]), $MachinePrecision] / N[Power[b, 3.0], $MachinePrecision]), $MachinePrecision] * c + N[(0.5 * N[(a / b), $MachinePrecision]), $MachinePrecision]), $MachinePrecision] * c + N[(-0.6666666666666666 * b), $MachinePrecision]), $MachinePrecision] / c), $MachinePrecision]), $MachinePrecision]
          
          \begin{array}{l}
          
          \\
          \frac{0.3333333333333333}{\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{0.375 \cdot \left(a \cdot a\right)}{{b}^{3}}, c, 0.5 \cdot \frac{a}{b}\right), c, -0.6666666666666666 \cdot b\right)}{c}}
          \end{array}
          
          Derivation
          1. Initial program 18.9%

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

              \[\leadsto \color{blue}{\frac{\left(-b\right) + \sqrt{b \cdot b - \left(3 \cdot a\right) \cdot c}}{3 \cdot a}} \]
            2. clear-numN/A

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

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

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

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

              \[\leadsto \color{blue}{\frac{\frac{1}{3}}{\frac{a}{\left(-b\right) + \sqrt{b \cdot b - \left(3 \cdot a\right) \cdot c}}}} \]
            7. metadata-evalN/A

              \[\leadsto \frac{\color{blue}{\frac{1}{3}}}{\frac{a}{\left(-b\right) + \sqrt{b \cdot b - \left(3 \cdot a\right) \cdot c}}} \]
            8. lower-/.f6418.9

              \[\leadsto \frac{0.3333333333333333}{\color{blue}{\frac{a}{\left(-b\right) + \sqrt{b \cdot b - \left(3 \cdot a\right) \cdot c}}}} \]
            9. lift-+.f64N/A

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

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

              \[\leadsto \frac{\frac{1}{3}}{\frac{a}{\sqrt{b \cdot b - \left(3 \cdot a\right) \cdot c} + \color{blue}{\left(\mathsf{neg}\left(b\right)\right)}}} \]
            12. unsub-negN/A

              \[\leadsto \frac{\frac{1}{3}}{\frac{a}{\color{blue}{\sqrt{b \cdot b - \left(3 \cdot a\right) \cdot c} - b}}} \]
            13. lower--.f6418.9

              \[\leadsto \frac{0.3333333333333333}{\frac{a}{\color{blue}{\sqrt{b \cdot b - \left(3 \cdot a\right) \cdot c} - b}}} \]
          4. Applied rewrites18.9%

            \[\leadsto \color{blue}{\frac{0.3333333333333333}{\frac{a}{\sqrt{\mathsf{fma}\left(-3 \cdot c, a, b \cdot b\right)} - b}}} \]
          5. Taylor expanded in c around 0

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

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

            \[\leadsto \frac{0.3333333333333333}{\color{blue}{\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{0.375 \cdot \left(a \cdot a\right)}{{b}^{3}}, c, \frac{a}{b} \cdot 0.5\right), c, -0.6666666666666666 \cdot b\right)}{c}}} \]
          8. Final simplification96.3%

            \[\leadsto \frac{0.3333333333333333}{\frac{\mathsf{fma}\left(\mathsf{fma}\left(\frac{0.375 \cdot \left(a \cdot a\right)}{{b}^{3}}, c, 0.5 \cdot \frac{a}{b}\right), c, -0.6666666666666666 \cdot b\right)}{c}} \]
          9. Add Preprocessing

          Alternative 5: 96.5% accurate, 0.3× speedup?

          \[\begin{array}{l} \\ \frac{0.3333333333333333}{\mathsf{fma}\left(\mathsf{fma}\left(\frac{c}{{b}^{3}} \cdot 0.375, a, \frac{0.5}{b}\right), a, \frac{b}{c} \cdot -0.6666666666666666\right)} \end{array} \]
          (FPCore (a b c)
           :precision binary64
           (/
            0.3333333333333333
            (fma
             (fma (* (/ c (pow b 3.0)) 0.375) a (/ 0.5 b))
             a
             (* (/ b c) -0.6666666666666666))))
          double code(double a, double b, double c) {
          	return 0.3333333333333333 / fma(fma(((c / pow(b, 3.0)) * 0.375), a, (0.5 / b)), a, ((b / c) * -0.6666666666666666));
          }
          
          function code(a, b, c)
          	return Float64(0.3333333333333333 / fma(fma(Float64(Float64(c / (b ^ 3.0)) * 0.375), a, Float64(0.5 / b)), a, Float64(Float64(b / c) * -0.6666666666666666)))
          end
          
          code[a_, b_, c_] := N[(0.3333333333333333 / N[(N[(N[(N[(c / N[Power[b, 3.0], $MachinePrecision]), $MachinePrecision] * 0.375), $MachinePrecision] * a + N[(0.5 / b), $MachinePrecision]), $MachinePrecision] * a + N[(N[(b / c), $MachinePrecision] * -0.6666666666666666), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
          
          \begin{array}{l}
          
          \\
          \frac{0.3333333333333333}{\mathsf{fma}\left(\mathsf{fma}\left(\frac{c}{{b}^{3}} \cdot 0.375, a, \frac{0.5}{b}\right), a, \frac{b}{c} \cdot -0.6666666666666666\right)}
          \end{array}
          
          Derivation
          1. Initial program 18.9%

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

              \[\leadsto \color{blue}{\frac{\left(-b\right) + \sqrt{b \cdot b - \left(3 \cdot a\right) \cdot c}}{3 \cdot a}} \]
            2. clear-numN/A

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

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

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

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

              \[\leadsto \color{blue}{\frac{\frac{1}{3}}{\frac{a}{\left(-b\right) + \sqrt{b \cdot b - \left(3 \cdot a\right) \cdot c}}}} \]
            7. metadata-evalN/A

              \[\leadsto \frac{\color{blue}{\frac{1}{3}}}{\frac{a}{\left(-b\right) + \sqrt{b \cdot b - \left(3 \cdot a\right) \cdot c}}} \]
            8. lower-/.f6418.9

              \[\leadsto \frac{0.3333333333333333}{\color{blue}{\frac{a}{\left(-b\right) + \sqrt{b \cdot b - \left(3 \cdot a\right) \cdot c}}}} \]
            9. lift-+.f64N/A

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

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

              \[\leadsto \frac{\frac{1}{3}}{\frac{a}{\sqrt{b \cdot b - \left(3 \cdot a\right) \cdot c} + \color{blue}{\left(\mathsf{neg}\left(b\right)\right)}}} \]
            12. unsub-negN/A

              \[\leadsto \frac{\frac{1}{3}}{\frac{a}{\color{blue}{\sqrt{b \cdot b - \left(3 \cdot a\right) \cdot c} - b}}} \]
            13. lower--.f6418.9

              \[\leadsto \frac{0.3333333333333333}{\frac{a}{\color{blue}{\sqrt{b \cdot b - \left(3 \cdot a\right) \cdot c} - b}}} \]
          4. Applied rewrites18.9%

            \[\leadsto \color{blue}{\frac{0.3333333333333333}{\frac{a}{\sqrt{\mathsf{fma}\left(-3 \cdot c, a, b \cdot b\right)} - b}}} \]
          5. Taylor expanded in a around 0

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

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

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

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

            \[\leadsto \frac{0.3333333333333333}{\color{blue}{\mathsf{fma}\left(\mathsf{fma}\left(0.375 \cdot \frac{c}{{b}^{3}}, a, \frac{0.5}{b}\right), a, \frac{b}{c} \cdot -0.6666666666666666\right)}} \]
          8. Final simplification96.2%

            \[\leadsto \frac{0.3333333333333333}{\mathsf{fma}\left(\mathsf{fma}\left(\frac{c}{{b}^{3}} \cdot 0.375, a, \frac{0.5}{b}\right), a, \frac{b}{c} \cdot -0.6666666666666666\right)} \]
          9. Add Preprocessing

          Alternative 6: 95.2% accurate, 1.0× speedup?

          \[\begin{array}{l} \\ \frac{\mathsf{fma}\left(-0.375 \cdot a, \frac{c \cdot c}{b \cdot b}, -0.5 \cdot c\right)}{b} \end{array} \]
          (FPCore (a b c)
           :precision binary64
           (/ (fma (* -0.375 a) (/ (* c c) (* b b)) (* -0.5 c)) b))
          double code(double a, double b, double c) {
          	return fma((-0.375 * a), ((c * c) / (b * b)), (-0.5 * c)) / b;
          }
          
          function code(a, b, c)
          	return Float64(fma(Float64(-0.375 * a), Float64(Float64(c * c) / Float64(b * b)), Float64(-0.5 * c)) / b)
          end
          
          code[a_, b_, c_] := N[(N[(N[(-0.375 * a), $MachinePrecision] * N[(N[(c * c), $MachinePrecision] / N[(b * b), $MachinePrecision]), $MachinePrecision] + N[(-0.5 * c), $MachinePrecision]), $MachinePrecision] / b), $MachinePrecision]
          
          \begin{array}{l}
          
          \\
          \frac{\mathsf{fma}\left(-0.375 \cdot a, \frac{c \cdot c}{b \cdot b}, -0.5 \cdot c\right)}{b}
          \end{array}
          
          Derivation
          1. Initial program 18.9%

            \[\frac{\left(-b\right) + \sqrt{b \cdot b - \left(3 \cdot a\right) \cdot c}}{3 \cdot a} \]
          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 rewrites96.5%

            \[\leadsto \color{blue}{\frac{\mathsf{fma}\left(\frac{-0.375 \cdot a}{b}, \frac{c \cdot c}{b}, \mathsf{fma}\left(\frac{\left({c}^{3} \cdot a\right) \cdot a}{{b}^{4}}, -0.5625, -0.5 \cdot c\right)\right)}{b}} \]
          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 rewrites94.5%

              \[\leadsto \frac{\mathsf{fma}\left(\frac{a}{b} \cdot -0.375, \frac{c}{b}, -0.5\right) \cdot c}{b} \]
            2. Step-by-step derivation
              1. Applied rewrites94.5%

                \[\leadsto \frac{\mathsf{fma}\left(a \cdot -0.375, \frac{c \cdot c}{b \cdot b}, -0.5 \cdot c\right)}{b} \]
              2. Final simplification94.5%

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

              Alternative 7: 95.0% accurate, 1.1× speedup?

              \[\begin{array}{l} \\ \frac{0.3333333333333333}{\mathsf{fma}\left(\frac{a}{b}, 0.5, \frac{b}{c} \cdot -0.6666666666666666\right)} \end{array} \]
              (FPCore (a b c)
               :precision binary64
               (/ 0.3333333333333333 (fma (/ a b) 0.5 (* (/ b c) -0.6666666666666666))))
              double code(double a, double b, double c) {
              	return 0.3333333333333333 / fma((a / b), 0.5, ((b / c) * -0.6666666666666666));
              }
              
              function code(a, b, c)
              	return Float64(0.3333333333333333 / fma(Float64(a / b), 0.5, Float64(Float64(b / c) * -0.6666666666666666)))
              end
              
              code[a_, b_, c_] := N[(0.3333333333333333 / N[(N[(a / b), $MachinePrecision] * 0.5 + N[(N[(b / c), $MachinePrecision] * -0.6666666666666666), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
              
              \begin{array}{l}
              
              \\
              \frac{0.3333333333333333}{\mathsf{fma}\left(\frac{a}{b}, 0.5, \frac{b}{c} \cdot -0.6666666666666666\right)}
              \end{array}
              
              Derivation
              1. Initial program 18.9%

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

                  \[\leadsto \color{blue}{\frac{\left(-b\right) + \sqrt{b \cdot b - \left(3 \cdot a\right) \cdot c}}{3 \cdot a}} \]
                2. clear-numN/A

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

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

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

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

                  \[\leadsto \color{blue}{\frac{\frac{1}{3}}{\frac{a}{\left(-b\right) + \sqrt{b \cdot b - \left(3 \cdot a\right) \cdot c}}}} \]
                7. metadata-evalN/A

                  \[\leadsto \frac{\color{blue}{\frac{1}{3}}}{\frac{a}{\left(-b\right) + \sqrt{b \cdot b - \left(3 \cdot a\right) \cdot c}}} \]
                8. lower-/.f6418.9

                  \[\leadsto \frac{0.3333333333333333}{\color{blue}{\frac{a}{\left(-b\right) + \sqrt{b \cdot b - \left(3 \cdot a\right) \cdot c}}}} \]
                9. lift-+.f64N/A

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

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

                  \[\leadsto \frac{\frac{1}{3}}{\frac{a}{\sqrt{b \cdot b - \left(3 \cdot a\right) \cdot c} + \color{blue}{\left(\mathsf{neg}\left(b\right)\right)}}} \]
                12. unsub-negN/A

                  \[\leadsto \frac{\frac{1}{3}}{\frac{a}{\color{blue}{\sqrt{b \cdot b - \left(3 \cdot a\right) \cdot c} - b}}} \]
                13. lower--.f6418.9

                  \[\leadsto \frac{0.3333333333333333}{\frac{a}{\color{blue}{\sqrt{b \cdot b - \left(3 \cdot a\right) \cdot c} - b}}} \]
              4. Applied rewrites18.9%

                \[\leadsto \color{blue}{\frac{0.3333333333333333}{\frac{a}{\sqrt{\mathsf{fma}\left(-3 \cdot c, a, b \cdot b\right)} - b}}} \]
              5. Taylor expanded in a around 0

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

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

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

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

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

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

                  \[\leadsto \frac{\frac{1}{3}}{\mathsf{fma}\left(\frac{a}{b}, \frac{1}{2}, \color{blue}{\frac{b}{c} \cdot \frac{-2}{3}}\right)} \]
                7. lower-/.f6494.3

                  \[\leadsto \frac{0.3333333333333333}{\mathsf{fma}\left(\frac{a}{b}, 0.5, \color{blue}{\frac{b}{c}} \cdot -0.6666666666666666\right)} \]
              7. Applied rewrites94.3%

                \[\leadsto \frac{0.3333333333333333}{\color{blue}{\mathsf{fma}\left(\frac{a}{b}, 0.5, \frac{b}{c} \cdot -0.6666666666666666\right)}} \]
              8. Add Preprocessing

              Alternative 8: 90.4% 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 18.9%

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

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

                  \[\leadsto \color{blue}{\frac{-1}{2} \cdot \frac{c}{b}} \]
                2. lower-/.f6489.5

                  \[\leadsto -0.5 \cdot \color{blue}{\frac{c}{b}} \]
              5. Applied rewrites89.5%

                \[\leadsto \color{blue}{-0.5 \cdot \frac{c}{b}} \]
              6. Add Preprocessing

              Alternative 9: 3.3% accurate, 50.0× speedup?

              \[\begin{array}{l} \\ 0 \end{array} \]
              (FPCore (a b c) :precision binary64 0.0)
              double code(double a, double b, double c) {
              	return 0.0;
              }
              
              real(8) function code(a, b, c)
                  real(8), intent (in) :: a
                  real(8), intent (in) :: b
                  real(8), intent (in) :: c
                  code = 0.0d0
              end function
              
              public static double code(double a, double b, double c) {
              	return 0.0;
              }
              
              def code(a, b, c):
              	return 0.0
              
              function code(a, b, c)
              	return 0.0
              end
              
              function tmp = code(a, b, c)
              	tmp = 0.0;
              end
              
              code[a_, b_, c_] := 0.0
              
              \begin{array}{l}
              
              \\
              0
              \end{array}
              
              Derivation
              1. Initial program 18.9%

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

                  \[\leadsto \color{blue}{\frac{\left(-b\right) + \sqrt{b \cdot b - \left(3 \cdot a\right) \cdot c}}{3 \cdot a}} \]
                2. clear-numN/A

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

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

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

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

                  \[\leadsto \color{blue}{\frac{\frac{1}{3}}{\frac{a}{\left(-b\right) + \sqrt{b \cdot b - \left(3 \cdot a\right) \cdot c}}}} \]
                7. metadata-evalN/A

                  \[\leadsto \frac{\color{blue}{\frac{1}{3}}}{\frac{a}{\left(-b\right) + \sqrt{b \cdot b - \left(3 \cdot a\right) \cdot c}}} \]
                8. lower-/.f6418.9

                  \[\leadsto \frac{0.3333333333333333}{\color{blue}{\frac{a}{\left(-b\right) + \sqrt{b \cdot b - \left(3 \cdot a\right) \cdot c}}}} \]
                9. lift-+.f64N/A

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

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

                  \[\leadsto \frac{\frac{1}{3}}{\frac{a}{\sqrt{b \cdot b - \left(3 \cdot a\right) \cdot c} + \color{blue}{\left(\mathsf{neg}\left(b\right)\right)}}} \]
                12. unsub-negN/A

                  \[\leadsto \frac{\frac{1}{3}}{\frac{a}{\color{blue}{\sqrt{b \cdot b - \left(3 \cdot a\right) \cdot c} - b}}} \]
                13. lower--.f6418.9

                  \[\leadsto \frac{0.3333333333333333}{\frac{a}{\color{blue}{\sqrt{b \cdot b - \left(3 \cdot a\right) \cdot c} - b}}} \]
              4. Applied rewrites18.9%

                \[\leadsto \color{blue}{\frac{0.3333333333333333}{\frac{a}{\sqrt{\mathsf{fma}\left(-3 \cdot c, a, b \cdot b\right)} - b}}} \]
              5. Step-by-step derivation
                1. lift-/.f64N/A

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

                  \[\leadsto \frac{\frac{1}{3}}{\color{blue}{\frac{a}{\sqrt{\mathsf{fma}\left(-3 \cdot c, a, b \cdot b\right)} - b}}} \]
                3. associate-/r/N/A

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

                  \[\leadsto \frac{\frac{1}{3}}{a} \cdot \color{blue}{\left(\sqrt{\mathsf{fma}\left(-3 \cdot c, a, b \cdot b\right)} - b\right)} \]
                5. sub-negN/A

                  \[\leadsto \frac{\frac{1}{3}}{a} \cdot \color{blue}{\left(\sqrt{\mathsf{fma}\left(-3 \cdot c, a, b \cdot b\right)} + \left(\mathsf{neg}\left(b\right)\right)\right)} \]
                6. distribute-lft-inN/A

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

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

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

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

                  \[\leadsto \frac{\frac{1}{3}}{a} \cdot \sqrt{\mathsf{fma}\left(-3 \cdot c, a, b \cdot b\right)} + \color{blue}{\frac{\frac{1}{3}}{a} \cdot \left(\mathsf{neg}\left(b\right)\right)} \]
                11. lower-/.f64N/A

                  \[\leadsto \frac{\frac{1}{3}}{a} \cdot \sqrt{\mathsf{fma}\left(-3 \cdot c, a, b \cdot b\right)} + \color{blue}{\frac{\frac{1}{3}}{a}} \cdot \left(\mathsf{neg}\left(b\right)\right) \]
                12. lower-neg.f6418.7

                  \[\leadsto \frac{0.3333333333333333}{a} \cdot \sqrt{\mathsf{fma}\left(-3 \cdot c, a, b \cdot b\right)} + \frac{0.3333333333333333}{a} \cdot \color{blue}{\left(-b\right)} \]
              6. Applied rewrites18.7%

                \[\leadsto \color{blue}{\frac{0.3333333333333333}{a} \cdot \sqrt{\mathsf{fma}\left(-3 \cdot c, a, b \cdot b\right)} + \frac{0.3333333333333333}{a} \cdot \left(-b\right)} \]
              7. Taylor expanded in c around 0

                \[\leadsto \color{blue}{\frac{-1}{3} \cdot \frac{b}{a} + \frac{1}{3} \cdot \frac{b}{a}} \]
              8. Step-by-step derivation
                1. distribute-rgt-outN/A

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

                  \[\leadsto \frac{b}{a} \cdot \color{blue}{0} \]
                3. mul0-rgt3.3

                  \[\leadsto \color{blue}{0} \]
              9. Applied rewrites3.3%

                \[\leadsto \color{blue}{0} \]
              10. Add Preprocessing

              Reproduce

              ?
              herbie shell --seed 2024283 
              (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)))