Cubic critical, medium range

Percentage Accurate: 31.5% → 95.3%
Time: 15.0s
Alternatives: 8
Speedup: 23.2×

Specification

?
\[\left(\left(1.1102230246251565 \cdot 10^{-16} < a \land a < 9007199254740992\right) \land \left(1.1102230246251565 \cdot 10^{-16} < b \land b < 9007199254740992\right)\right) \land \left(1.1102230246251565 \cdot 10^{-16} < c \land c < 9007199254740992\right)\]
\[\begin{array}{l} \\ \frac{\left(-b\right) + \sqrt{b \cdot b - \left(3 \cdot a\right) \cdot c}}{3 \cdot a} \end{array} \]
(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 8 alternatives:

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

Initial Program: 31.5% 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: 95.3% accurate, 0.2× speedup?

\[\begin{array}{l} \\ -0.5625 \cdot \frac{{a}^{2} \cdot {c}^{3}}{{b}^{5}} + \left(-0.5 \cdot \frac{c}{b} + \left(-0.375 \cdot \frac{a \cdot {c}^{2}}{{b}^{3}} + \frac{-1.0546875 \cdot {\left(a \cdot c\right)}^{4}}{a \cdot {b}^{7}}\right)\right) \end{array} \]
(FPCore (a b c)
 :precision binary64
 (+
  (* -0.5625 (/ (* (pow a 2.0) (pow c 3.0)) (pow b 5.0)))
  (+
   (* -0.5 (/ c b))
   (+
    (* -0.375 (/ (* a (pow c 2.0)) (pow b 3.0)))
    (/ (* -1.0546875 (pow (* a c) 4.0)) (* a (pow b 7.0)))))))
double code(double a, double b, double c) {
	return (-0.5625 * ((pow(a, 2.0) * pow(c, 3.0)) / pow(b, 5.0))) + ((-0.5 * (c / b)) + ((-0.375 * ((a * pow(c, 2.0)) / pow(b, 3.0))) + ((-1.0546875 * pow((a * c), 4.0)) / (a * pow(b, 7.0)))));
}
real(8) function code(a, b, c)
    real(8), intent (in) :: a
    real(8), intent (in) :: b
    real(8), intent (in) :: c
    code = ((-0.5625d0) * (((a ** 2.0d0) * (c ** 3.0d0)) / (b ** 5.0d0))) + (((-0.5d0) * (c / b)) + (((-0.375d0) * ((a * (c ** 2.0d0)) / (b ** 3.0d0))) + (((-1.0546875d0) * ((a * c) ** 4.0d0)) / (a * (b ** 7.0d0)))))
end function
public static double code(double a, double b, double c) {
	return (-0.5625 * ((Math.pow(a, 2.0) * Math.pow(c, 3.0)) / Math.pow(b, 5.0))) + ((-0.5 * (c / b)) + ((-0.375 * ((a * Math.pow(c, 2.0)) / Math.pow(b, 3.0))) + ((-1.0546875 * Math.pow((a * c), 4.0)) / (a * Math.pow(b, 7.0)))));
}
def code(a, b, c):
	return (-0.5625 * ((math.pow(a, 2.0) * math.pow(c, 3.0)) / math.pow(b, 5.0))) + ((-0.5 * (c / b)) + ((-0.375 * ((a * math.pow(c, 2.0)) / math.pow(b, 3.0))) + ((-1.0546875 * math.pow((a * c), 4.0)) / (a * math.pow(b, 7.0)))))
function code(a, b, c)
	return Float64(Float64(-0.5625 * Float64(Float64((a ^ 2.0) * (c ^ 3.0)) / (b ^ 5.0))) + Float64(Float64(-0.5 * Float64(c / b)) + Float64(Float64(-0.375 * Float64(Float64(a * (c ^ 2.0)) / (b ^ 3.0))) + Float64(Float64(-1.0546875 * (Float64(a * c) ^ 4.0)) / Float64(a * (b ^ 7.0))))))
end
function tmp = code(a, b, c)
	tmp = (-0.5625 * (((a ^ 2.0) * (c ^ 3.0)) / (b ^ 5.0))) + ((-0.5 * (c / b)) + ((-0.375 * ((a * (c ^ 2.0)) / (b ^ 3.0))) + ((-1.0546875 * ((a * c) ^ 4.0)) / (a * (b ^ 7.0)))));
end
code[a_, b_, c_] := N[(N[(-0.5625 * N[(N[(N[Power[a, 2.0], $MachinePrecision] * N[Power[c, 3.0], $MachinePrecision]), $MachinePrecision] / N[Power[b, 5.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + N[(N[(-0.5 * N[(c / b), $MachinePrecision]), $MachinePrecision] + N[(N[(-0.375 * N[(N[(a * N[Power[c, 2.0], $MachinePrecision]), $MachinePrecision] / N[Power[b, 3.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + N[(N[(-1.0546875 * N[Power[N[(a * c), $MachinePrecision], 4.0], $MachinePrecision]), $MachinePrecision] / N[(a * N[Power[b, 7.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
\begin{array}{l}

\\
-0.5625 \cdot \frac{{a}^{2} \cdot {c}^{3}}{{b}^{5}} + \left(-0.5 \cdot \frac{c}{b} + \left(-0.375 \cdot \frac{a \cdot {c}^{2}}{{b}^{3}} + \frac{-1.0546875 \cdot {\left(a \cdot c\right)}^{4}}{a \cdot {b}^{7}}\right)\right)
\end{array}
Derivation
  1. Initial program 31.1%

    \[\frac{\left(-b\right) + \sqrt{b \cdot b - \left(3 \cdot a\right) \cdot c}}{3 \cdot a} \]
  2. Taylor expanded in b around inf 94.7%

    \[\leadsto \color{blue}{-0.5625 \cdot \frac{{a}^{2} \cdot {c}^{3}}{{b}^{5}} + \left(-0.5 \cdot \frac{c}{b} + \left(-0.375 \cdot \frac{a \cdot {c}^{2}}{{b}^{3}} + -0.16666666666666666 \cdot \frac{5.0625 \cdot \left({a}^{4} \cdot {c}^{4}\right) + {\left(-1.125 \cdot \left({a}^{2} \cdot {c}^{2}\right)\right)}^{2}}{a \cdot {b}^{7}}\right)\right)} \]
  3. Taylor expanded in c around 0 94.7%

    \[\leadsto -0.5625 \cdot \frac{{a}^{2} \cdot {c}^{3}}{{b}^{5}} + \left(-0.5 \cdot \frac{c}{b} + \left(-0.375 \cdot \frac{a \cdot {c}^{2}}{{b}^{3}} + \color{blue}{-0.16666666666666666 \cdot \frac{{c}^{4} \cdot \left(1.265625 \cdot {a}^{4} + 5.0625 \cdot {a}^{4}\right)}{a \cdot {b}^{7}}}\right)\right) \]
  4. Step-by-step derivation
    1. Simplified94.7%

      \[\leadsto -0.5625 \cdot \frac{{a}^{2} \cdot {c}^{3}}{{b}^{5}} + \left(-0.5 \cdot \frac{c}{b} + \left(-0.375 \cdot \frac{a \cdot {c}^{2}}{{b}^{3}} + \color{blue}{-0.16666666666666666 \cdot \frac{{\left(a \cdot c\right)}^{4} \cdot 6.328125}{a \cdot {b}^{7}}}\right)\right) \]
    2. Step-by-step derivation
      1. associate-*r/94.7%

        \[\leadsto -0.5625 \cdot \frac{{a}^{2} \cdot {c}^{3}}{{b}^{5}} + \left(-0.5 \cdot \frac{c}{b} + \left(-0.375 \cdot \frac{a \cdot {c}^{2}}{{b}^{3}} + \color{blue}{\frac{-0.16666666666666666 \cdot \left({\left(a \cdot c\right)}^{4} \cdot 6.328125\right)}{a \cdot {b}^{7}}}\right)\right) \]
    3. Applied egg-rr94.7%

      \[\leadsto -0.5625 \cdot \frac{{a}^{2} \cdot {c}^{3}}{{b}^{5}} + \left(-0.5 \cdot \frac{c}{b} + \left(-0.375 \cdot \frac{a \cdot {c}^{2}}{{b}^{3}} + \color{blue}{\frac{-0.16666666666666666 \cdot \left({\left(a \cdot c\right)}^{4} \cdot 6.328125\right)}{a \cdot {b}^{7}}}\right)\right) \]
    4. Step-by-step derivation
      1. *-commutative94.7%

        \[\leadsto -0.5625 \cdot \frac{{a}^{2} \cdot {c}^{3}}{{b}^{5}} + \left(-0.5 \cdot \frac{c}{b} + \left(-0.375 \cdot \frac{a \cdot {c}^{2}}{{b}^{3}} + \frac{-0.16666666666666666 \cdot \color{blue}{\left(6.328125 \cdot {\left(a \cdot c\right)}^{4}\right)}}{a \cdot {b}^{7}}\right)\right) \]
      2. associate-*r*94.7%

        \[\leadsto -0.5625 \cdot \frac{{a}^{2} \cdot {c}^{3}}{{b}^{5}} + \left(-0.5 \cdot \frac{c}{b} + \left(-0.375 \cdot \frac{a \cdot {c}^{2}}{{b}^{3}} + \frac{\color{blue}{\left(-0.16666666666666666 \cdot 6.328125\right) \cdot {\left(a \cdot c\right)}^{4}}}{a \cdot {b}^{7}}\right)\right) \]
      3. metadata-eval94.7%

        \[\leadsto -0.5625 \cdot \frac{{a}^{2} \cdot {c}^{3}}{{b}^{5}} + \left(-0.5 \cdot \frac{c}{b} + \left(-0.375 \cdot \frac{a \cdot {c}^{2}}{{b}^{3}} + \frac{\color{blue}{-1.0546875} \cdot {\left(a \cdot c\right)}^{4}}{a \cdot {b}^{7}}\right)\right) \]
    5. Simplified94.7%

      \[\leadsto -0.5625 \cdot \frac{{a}^{2} \cdot {c}^{3}}{{b}^{5}} + \left(-0.5 \cdot \frac{c}{b} + \left(-0.375 \cdot \frac{a \cdot {c}^{2}}{{b}^{3}} + \color{blue}{\frac{-1.0546875 \cdot {\left(a \cdot c\right)}^{4}}{a \cdot {b}^{7}}}\right)\right) \]
    6. Final simplification94.7%

      \[\leadsto -0.5625 \cdot \frac{{a}^{2} \cdot {c}^{3}}{{b}^{5}} + \left(-0.5 \cdot \frac{c}{b} + \left(-0.375 \cdot \frac{a \cdot {c}^{2}}{{b}^{3}} + \frac{-1.0546875 \cdot {\left(a \cdot c\right)}^{4}}{a \cdot {b}^{7}}\right)\right) \]

    Alternative 2: 93.8% accurate, 0.2× speedup?

    \[\begin{array}{l} \\ -0.5625 \cdot \frac{{a}^{2} \cdot {c}^{3}}{{b}^{5}} + \left(-0.5 \cdot \frac{c}{b} + -0.375 \cdot \frac{a \cdot {c}^{2}}{{b}^{3}}\right) \end{array} \]
    (FPCore (a b c)
     :precision binary64
     (+
      (* -0.5625 (/ (* (pow a 2.0) (pow c 3.0)) (pow b 5.0)))
      (+ (* -0.5 (/ c b)) (* -0.375 (/ (* a (pow c 2.0)) (pow b 3.0))))))
    double code(double a, double b, double c) {
    	return (-0.5625 * ((pow(a, 2.0) * pow(c, 3.0)) / pow(b, 5.0))) + ((-0.5 * (c / b)) + (-0.375 * ((a * pow(c, 2.0)) / pow(b, 3.0))));
    }
    
    real(8) function code(a, b, c)
        real(8), intent (in) :: a
        real(8), intent (in) :: b
        real(8), intent (in) :: c
        code = ((-0.5625d0) * (((a ** 2.0d0) * (c ** 3.0d0)) / (b ** 5.0d0))) + (((-0.5d0) * (c / b)) + ((-0.375d0) * ((a * (c ** 2.0d0)) / (b ** 3.0d0))))
    end function
    
    public static double code(double a, double b, double c) {
    	return (-0.5625 * ((Math.pow(a, 2.0) * Math.pow(c, 3.0)) / Math.pow(b, 5.0))) + ((-0.5 * (c / b)) + (-0.375 * ((a * Math.pow(c, 2.0)) / Math.pow(b, 3.0))));
    }
    
    def code(a, b, c):
    	return (-0.5625 * ((math.pow(a, 2.0) * math.pow(c, 3.0)) / math.pow(b, 5.0))) + ((-0.5 * (c / b)) + (-0.375 * ((a * math.pow(c, 2.0)) / math.pow(b, 3.0))))
    
    function code(a, b, c)
    	return Float64(Float64(-0.5625 * Float64(Float64((a ^ 2.0) * (c ^ 3.0)) / (b ^ 5.0))) + Float64(Float64(-0.5 * Float64(c / b)) + Float64(-0.375 * Float64(Float64(a * (c ^ 2.0)) / (b ^ 3.0)))))
    end
    
    function tmp = code(a, b, c)
    	tmp = (-0.5625 * (((a ^ 2.0) * (c ^ 3.0)) / (b ^ 5.0))) + ((-0.5 * (c / b)) + (-0.375 * ((a * (c ^ 2.0)) / (b ^ 3.0))));
    end
    
    code[a_, b_, c_] := N[(N[(-0.5625 * N[(N[(N[Power[a, 2.0], $MachinePrecision] * N[Power[c, 3.0], $MachinePrecision]), $MachinePrecision] / N[Power[b, 5.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision] + N[(N[(-0.5 * N[(c / b), $MachinePrecision]), $MachinePrecision] + N[(-0.375 * N[(N[(a * N[Power[c, 2.0], $MachinePrecision]), $MachinePrecision] / N[Power[b, 3.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
    
    \begin{array}{l}
    
    \\
    -0.5625 \cdot \frac{{a}^{2} \cdot {c}^{3}}{{b}^{5}} + \left(-0.5 \cdot \frac{c}{b} + -0.375 \cdot \frac{a \cdot {c}^{2}}{{b}^{3}}\right)
    \end{array}
    
    Derivation
    1. Initial program 31.1%

      \[\frac{\left(-b\right) + \sqrt{b \cdot b - \left(3 \cdot a\right) \cdot c}}{3 \cdot a} \]
    2. Taylor expanded in b around inf 92.9%

      \[\leadsto \color{blue}{-0.5625 \cdot \frac{{a}^{2} \cdot {c}^{3}}{{b}^{5}} + \left(-0.5 \cdot \frac{c}{b} + -0.375 \cdot \frac{a \cdot {c}^{2}}{{b}^{3}}\right)} \]
    3. Final simplification92.9%

      \[\leadsto -0.5625 \cdot \frac{{a}^{2} \cdot {c}^{3}}{{b}^{5}} + \left(-0.5 \cdot \frac{c}{b} + -0.375 \cdot \frac{a \cdot {c}^{2}}{{b}^{3}}\right) \]

    Alternative 3: 84.2% accurate, 0.4× speedup?

    \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;\frac{\sqrt{b \cdot b - c \cdot \left(a \cdot 3\right)} - b}{a \cdot 3} \leq -6 \cdot 10^{-7}:\\ \;\;\;\;\frac{\sqrt{\mathsf{fma}\left(a, c \cdot -3, b \cdot b\right)} - b}{a \cdot 3}\\ \mathbf{else}:\\ \;\;\;\;-0.5 \cdot \frac{c}{b}\\ \end{array} \end{array} \]
    (FPCore (a b c)
     :precision binary64
     (if (<= (/ (- (sqrt (- (* b b) (* c (* a 3.0)))) b) (* a 3.0)) -6e-7)
       (/ (- (sqrt (fma a (* c -3.0) (* b b))) b) (* a 3.0))
       (* -0.5 (/ c b))))
    double code(double a, double b, double c) {
    	double tmp;
    	if (((sqrt(((b * b) - (c * (a * 3.0)))) - b) / (a * 3.0)) <= -6e-7) {
    		tmp = (sqrt(fma(a, (c * -3.0), (b * b))) - b) / (a * 3.0);
    	} else {
    		tmp = -0.5 * (c / b);
    	}
    	return tmp;
    }
    
    function code(a, b, c)
    	tmp = 0.0
    	if (Float64(Float64(sqrt(Float64(Float64(b * b) - Float64(c * Float64(a * 3.0)))) - b) / Float64(a * 3.0)) <= -6e-7)
    		tmp = Float64(Float64(sqrt(fma(a, Float64(c * -3.0), Float64(b * b))) - b) / Float64(a * 3.0));
    	else
    		tmp = Float64(-0.5 * Float64(c / b));
    	end
    	return tmp
    end
    
    code[a_, b_, c_] := If[LessEqual[N[(N[(N[Sqrt[N[(N[(b * b), $MachinePrecision] - N[(c * N[(a * 3.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision] - b), $MachinePrecision] / N[(a * 3.0), $MachinePrecision]), $MachinePrecision], -6e-7], N[(N[(N[Sqrt[N[(a * N[(c * -3.0), $MachinePrecision] + N[(b * b), $MachinePrecision]), $MachinePrecision]], $MachinePrecision] - b), $MachinePrecision] / N[(a * 3.0), $MachinePrecision]), $MachinePrecision], N[(-0.5 * N[(c / b), $MachinePrecision]), $MachinePrecision]]
    
    \begin{array}{l}
    
    \\
    \begin{array}{l}
    \mathbf{if}\;\frac{\sqrt{b \cdot b - c \cdot \left(a \cdot 3\right)} - b}{a \cdot 3} \leq -6 \cdot 10^{-7}:\\
    \;\;\;\;\frac{\sqrt{\mathsf{fma}\left(a, c \cdot -3, b \cdot b\right)} - b}{a \cdot 3}\\
    
    \mathbf{else}:\\
    \;\;\;\;-0.5 \cdot \frac{c}{b}\\
    
    
    \end{array}
    \end{array}
    
    Derivation
    1. Split input into 2 regimes
    2. if (/.f64 (+.f64 (neg.f64 b) (sqrt.f64 (-.f64 (*.f64 b b) (*.f64 (*.f64 3 a) c)))) (*.f64 3 a)) < -5.9999999999999997e-7

      1. Initial program 68.5%

        \[\frac{\left(-b\right) + \sqrt{b \cdot b - \left(3 \cdot a\right) \cdot c}}{3 \cdot a} \]
      2. Step-by-step derivation
        1. Simplified68.6%

          \[\leadsto \color{blue}{\frac{\sqrt{\mathsf{fma}\left(a, c \cdot -3, b \cdot b\right)} - b}{3 \cdot a}} \]

        if -5.9999999999999997e-7 < (/.f64 (+.f64 (neg.f64 b) (sqrt.f64 (-.f64 (*.f64 b b) (*.f64 (*.f64 3 a) c)))) (*.f64 3 a))

        1. Initial program 15.3%

          \[\frac{\left(-b\right) + \sqrt{b \cdot b - \left(3 \cdot a\right) \cdot c}}{3 \cdot a} \]
        2. Taylor expanded in b around inf 92.8%

          \[\leadsto \color{blue}{-0.5 \cdot \frac{c}{b}} \]
      3. Recombined 2 regimes into one program.
      4. Final simplification85.6%

        \[\leadsto \begin{array}{l} \mathbf{if}\;\frac{\sqrt{b \cdot b - c \cdot \left(a \cdot 3\right)} - b}{a \cdot 3} \leq -6 \cdot 10^{-7}:\\ \;\;\;\;\frac{\sqrt{\mathsf{fma}\left(a, c \cdot -3, b \cdot b\right)} - b}{a \cdot 3}\\ \mathbf{else}:\\ \;\;\;\;-0.5 \cdot \frac{c}{b}\\ \end{array} \]

      Alternative 4: 84.2% accurate, 0.4× speedup?

      \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;\frac{\sqrt{b \cdot b - c \cdot \left(a \cdot 3\right)} - b}{a \cdot 3} \leq -6 \cdot 10^{-7}:\\ \;\;\;\;\frac{\sqrt{\mathsf{fma}\left(b, b, c \cdot \left(a \cdot -3\right)\right)} - b}{a \cdot 3}\\ \mathbf{else}:\\ \;\;\;\;-0.5 \cdot \frac{c}{b}\\ \end{array} \end{array} \]
      (FPCore (a b c)
       :precision binary64
       (if (<= (/ (- (sqrt (- (* b b) (* c (* a 3.0)))) b) (* a 3.0)) -6e-7)
         (/ (- (sqrt (fma b b (* c (* a -3.0)))) b) (* a 3.0))
         (* -0.5 (/ c b))))
      double code(double a, double b, double c) {
      	double tmp;
      	if (((sqrt(((b * b) - (c * (a * 3.0)))) - b) / (a * 3.0)) <= -6e-7) {
      		tmp = (sqrt(fma(b, b, (c * (a * -3.0)))) - b) / (a * 3.0);
      	} else {
      		tmp = -0.5 * (c / b);
      	}
      	return tmp;
      }
      
      function code(a, b, c)
      	tmp = 0.0
      	if (Float64(Float64(sqrt(Float64(Float64(b * b) - Float64(c * Float64(a * 3.0)))) - b) / Float64(a * 3.0)) <= -6e-7)
      		tmp = Float64(Float64(sqrt(fma(b, b, Float64(c * Float64(a * -3.0)))) - b) / Float64(a * 3.0));
      	else
      		tmp = Float64(-0.5 * Float64(c / b));
      	end
      	return tmp
      end
      
      code[a_, b_, c_] := If[LessEqual[N[(N[(N[Sqrt[N[(N[(b * b), $MachinePrecision] - N[(c * N[(a * 3.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision] - b), $MachinePrecision] / N[(a * 3.0), $MachinePrecision]), $MachinePrecision], -6e-7], N[(N[(N[Sqrt[N[(b * b + N[(c * N[(a * -3.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision] - b), $MachinePrecision] / N[(a * 3.0), $MachinePrecision]), $MachinePrecision], N[(-0.5 * N[(c / b), $MachinePrecision]), $MachinePrecision]]
      
      \begin{array}{l}
      
      \\
      \begin{array}{l}
      \mathbf{if}\;\frac{\sqrt{b \cdot b - c \cdot \left(a \cdot 3\right)} - b}{a \cdot 3} \leq -6 \cdot 10^{-7}:\\
      \;\;\;\;\frac{\sqrt{\mathsf{fma}\left(b, b, c \cdot \left(a \cdot -3\right)\right)} - b}{a \cdot 3}\\
      
      \mathbf{else}:\\
      \;\;\;\;-0.5 \cdot \frac{c}{b}\\
      
      
      \end{array}
      \end{array}
      
      Derivation
      1. Split input into 2 regimes
      2. if (/.f64 (+.f64 (neg.f64 b) (sqrt.f64 (-.f64 (*.f64 b b) (*.f64 (*.f64 3 a) c)))) (*.f64 3 a)) < -5.9999999999999997e-7

        1. Initial program 68.5%

          \[\frac{\left(-b\right) + \sqrt{b \cdot b - \left(3 \cdot a\right) \cdot c}}{3 \cdot a} \]
        2. Step-by-step derivation
          1. Simplified68.6%

            \[\leadsto \color{blue}{\frac{\sqrt{\mathsf{fma}\left(b, b, c \cdot \left(a \cdot -3\right)\right)} - b}{3 \cdot a}} \]

          if -5.9999999999999997e-7 < (/.f64 (+.f64 (neg.f64 b) (sqrt.f64 (-.f64 (*.f64 b b) (*.f64 (*.f64 3 a) c)))) (*.f64 3 a))

          1. Initial program 15.3%

            \[\frac{\left(-b\right) + \sqrt{b \cdot b - \left(3 \cdot a\right) \cdot c}}{3 \cdot a} \]
          2. Taylor expanded in b around inf 92.8%

            \[\leadsto \color{blue}{-0.5 \cdot \frac{c}{b}} \]
        3. Recombined 2 regimes into one program.
        4. Final simplification85.6%

          \[\leadsto \begin{array}{l} \mathbf{if}\;\frac{\sqrt{b \cdot b - c \cdot \left(a \cdot 3\right)} - b}{a \cdot 3} \leq -6 \cdot 10^{-7}:\\ \;\;\;\;\frac{\sqrt{\mathsf{fma}\left(b, b, c \cdot \left(a \cdot -3\right)\right)} - b}{a \cdot 3}\\ \mathbf{else}:\\ \;\;\;\;-0.5 \cdot \frac{c}{b}\\ \end{array} \]

        Alternative 5: 84.2% accurate, 0.5× speedup?

        \[\begin{array}{l} \\ \begin{array}{l} \mathbf{if}\;\frac{\sqrt{b \cdot b - c \cdot \left(a \cdot 3\right)} - b}{a \cdot 3} \leq -6 \cdot 10^{-7}:\\ \;\;\;\;\frac{\sqrt{b \cdot b - a \cdot \left(c \cdot 3\right)} - b}{a \cdot 3}\\ \mathbf{else}:\\ \;\;\;\;-0.5 \cdot \frac{c}{b}\\ \end{array} \end{array} \]
        (FPCore (a b c)
         :precision binary64
         (if (<= (/ (- (sqrt (- (* b b) (* c (* a 3.0)))) b) (* a 3.0)) -6e-7)
           (/ (- (sqrt (- (* b b) (* a (* c 3.0)))) b) (* a 3.0))
           (* -0.5 (/ c b))))
        double code(double a, double b, double c) {
        	double tmp;
        	if (((sqrt(((b * b) - (c * (a * 3.0)))) - b) / (a * 3.0)) <= -6e-7) {
        		tmp = (sqrt(((b * b) - (a * (c * 3.0)))) - b) / (a * 3.0);
        	} else {
        		tmp = -0.5 * (c / b);
        	}
        	return tmp;
        }
        
        real(8) function code(a, b, c)
            real(8), intent (in) :: a
            real(8), intent (in) :: b
            real(8), intent (in) :: c
            real(8) :: tmp
            if (((sqrt(((b * b) - (c * (a * 3.0d0)))) - b) / (a * 3.0d0)) <= (-6d-7)) then
                tmp = (sqrt(((b * b) - (a * (c * 3.0d0)))) - b) / (a * 3.0d0)
            else
                tmp = (-0.5d0) * (c / b)
            end if
            code = tmp
        end function
        
        public static double code(double a, double b, double c) {
        	double tmp;
        	if (((Math.sqrt(((b * b) - (c * (a * 3.0)))) - b) / (a * 3.0)) <= -6e-7) {
        		tmp = (Math.sqrt(((b * b) - (a * (c * 3.0)))) - b) / (a * 3.0);
        	} else {
        		tmp = -0.5 * (c / b);
        	}
        	return tmp;
        }
        
        def code(a, b, c):
        	tmp = 0
        	if ((math.sqrt(((b * b) - (c * (a * 3.0)))) - b) / (a * 3.0)) <= -6e-7:
        		tmp = (math.sqrt(((b * b) - (a * (c * 3.0)))) - b) / (a * 3.0)
        	else:
        		tmp = -0.5 * (c / b)
        	return tmp
        
        function code(a, b, c)
        	tmp = 0.0
        	if (Float64(Float64(sqrt(Float64(Float64(b * b) - Float64(c * Float64(a * 3.0)))) - b) / Float64(a * 3.0)) <= -6e-7)
        		tmp = Float64(Float64(sqrt(Float64(Float64(b * b) - Float64(a * Float64(c * 3.0)))) - b) / Float64(a * 3.0));
        	else
        		tmp = Float64(-0.5 * Float64(c / b));
        	end
        	return tmp
        end
        
        function tmp_2 = code(a, b, c)
        	tmp = 0.0;
        	if (((sqrt(((b * b) - (c * (a * 3.0)))) - b) / (a * 3.0)) <= -6e-7)
        		tmp = (sqrt(((b * b) - (a * (c * 3.0)))) - b) / (a * 3.0);
        	else
        		tmp = -0.5 * (c / b);
        	end
        	tmp_2 = tmp;
        end
        
        code[a_, b_, c_] := If[LessEqual[N[(N[(N[Sqrt[N[(N[(b * b), $MachinePrecision] - N[(c * N[(a * 3.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision] - b), $MachinePrecision] / N[(a * 3.0), $MachinePrecision]), $MachinePrecision], -6e-7], N[(N[(N[Sqrt[N[(N[(b * b), $MachinePrecision] - N[(a * N[(c * 3.0), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]], $MachinePrecision] - b), $MachinePrecision] / N[(a * 3.0), $MachinePrecision]), $MachinePrecision], N[(-0.5 * N[(c / b), $MachinePrecision]), $MachinePrecision]]
        
        \begin{array}{l}
        
        \\
        \begin{array}{l}
        \mathbf{if}\;\frac{\sqrt{b \cdot b - c \cdot \left(a \cdot 3\right)} - b}{a \cdot 3} \leq -6 \cdot 10^{-7}:\\
        \;\;\;\;\frac{\sqrt{b \cdot b - a \cdot \left(c \cdot 3\right)} - b}{a \cdot 3}\\
        
        \mathbf{else}:\\
        \;\;\;\;-0.5 \cdot \frac{c}{b}\\
        
        
        \end{array}
        \end{array}
        
        Derivation
        1. Split input into 2 regimes
        2. if (/.f64 (+.f64 (neg.f64 b) (sqrt.f64 (-.f64 (*.f64 b b) (*.f64 (*.f64 3 a) c)))) (*.f64 3 a)) < -5.9999999999999997e-7

          1. Initial program 68.5%

            \[\frac{\left(-b\right) + \sqrt{b \cdot b - \left(3 \cdot a\right) \cdot c}}{3 \cdot a} \]
          2. Taylor expanded in a around 0 68.5%

            \[\leadsto \frac{\left(-b\right) + \sqrt{b \cdot b - \color{blue}{3 \cdot \left(a \cdot c\right)}}}{3 \cdot a} \]
          3. Step-by-step derivation
            1. *-commutative68.5%

              \[\leadsto \frac{\left(-b\right) + \sqrt{b \cdot b - \color{blue}{\left(a \cdot c\right) \cdot 3}}}{3 \cdot a} \]
          4. Simplified68.5%

            \[\leadsto \frac{\left(-b\right) + \sqrt{b \cdot b - \color{blue}{\left(a \cdot c\right) \cdot 3}}}{3 \cdot a} \]
          5. Taylor expanded in a around 0 68.5%

            \[\leadsto \frac{\left(-b\right) + \sqrt{b \cdot b - \color{blue}{3 \cdot \left(a \cdot c\right)}}}{3 \cdot a} \]
          6. Step-by-step derivation
            1. *-commutative68.5%

              \[\leadsto \frac{\left(-b\right) + \sqrt{b \cdot b - \color{blue}{\left(a \cdot c\right) \cdot 3}}}{3 \cdot a} \]
            2. associate-*r*68.6%

              \[\leadsto \frac{\left(-b\right) + \sqrt{b \cdot b - \color{blue}{a \cdot \left(c \cdot 3\right)}}}{3 \cdot a} \]
          7. Simplified68.6%

            \[\leadsto \frac{\left(-b\right) + \sqrt{b \cdot b - \color{blue}{a \cdot \left(c \cdot 3\right)}}}{3 \cdot a} \]

          if -5.9999999999999997e-7 < (/.f64 (+.f64 (neg.f64 b) (sqrt.f64 (-.f64 (*.f64 b b) (*.f64 (*.f64 3 a) c)))) (*.f64 3 a))

          1. Initial program 15.3%

            \[\frac{\left(-b\right) + \sqrt{b \cdot b - \left(3 \cdot a\right) \cdot c}}{3 \cdot a} \]
          2. Taylor expanded in b around inf 92.8%

            \[\leadsto \color{blue}{-0.5 \cdot \frac{c}{b}} \]
        3. Recombined 2 regimes into one program.
        4. Final simplification85.6%

          \[\leadsto \begin{array}{l} \mathbf{if}\;\frac{\sqrt{b \cdot b - c \cdot \left(a \cdot 3\right)} - b}{a \cdot 3} \leq -6 \cdot 10^{-7}:\\ \;\;\;\;\frac{\sqrt{b \cdot b - a \cdot \left(c \cdot 3\right)} - b}{a \cdot 3}\\ \mathbf{else}:\\ \;\;\;\;-0.5 \cdot \frac{c}{b}\\ \end{array} \]

        Alternative 6: 90.7% accurate, 0.5× speedup?

        \[\begin{array}{l} \\ -0.5 \cdot \frac{c}{b} + -0.375 \cdot \frac{a \cdot {c}^{2}}{{b}^{3}} \end{array} \]
        (FPCore (a b c)
         :precision binary64
         (+ (* -0.5 (/ c b)) (* -0.375 (/ (* a (pow c 2.0)) (pow b 3.0)))))
        double code(double a, double b, double c) {
        	return (-0.5 * (c / b)) + (-0.375 * ((a * pow(c, 2.0)) / pow(b, 3.0)));
        }
        
        real(8) function code(a, b, c)
            real(8), intent (in) :: a
            real(8), intent (in) :: b
            real(8), intent (in) :: c
            code = ((-0.5d0) * (c / b)) + ((-0.375d0) * ((a * (c ** 2.0d0)) / (b ** 3.0d0)))
        end function
        
        public static double code(double a, double b, double c) {
        	return (-0.5 * (c / b)) + (-0.375 * ((a * Math.pow(c, 2.0)) / Math.pow(b, 3.0)));
        }
        
        def code(a, b, c):
        	return (-0.5 * (c / b)) + (-0.375 * ((a * math.pow(c, 2.0)) / math.pow(b, 3.0)))
        
        function code(a, b, c)
        	return Float64(Float64(-0.5 * Float64(c / b)) + Float64(-0.375 * Float64(Float64(a * (c ^ 2.0)) / (b ^ 3.0))))
        end
        
        function tmp = code(a, b, c)
        	tmp = (-0.5 * (c / b)) + (-0.375 * ((a * (c ^ 2.0)) / (b ^ 3.0)));
        end
        
        code[a_, b_, c_] := N[(N[(-0.5 * N[(c / b), $MachinePrecision]), $MachinePrecision] + N[(-0.375 * N[(N[(a * N[Power[c, 2.0], $MachinePrecision]), $MachinePrecision] / N[Power[b, 3.0], $MachinePrecision]), $MachinePrecision]), $MachinePrecision]), $MachinePrecision]
        
        \begin{array}{l}
        
        \\
        -0.5 \cdot \frac{c}{b} + -0.375 \cdot \frac{a \cdot {c}^{2}}{{b}^{3}}
        \end{array}
        
        Derivation
        1. Initial program 31.1%

          \[\frac{\left(-b\right) + \sqrt{b \cdot b - \left(3 \cdot a\right) \cdot c}}{3 \cdot a} \]
        2. Taylor expanded in b around inf 89.9%

          \[\leadsto \color{blue}{-0.5 \cdot \frac{c}{b} + -0.375 \cdot \frac{a \cdot {c}^{2}}{{b}^{3}}} \]
        3. Final simplification89.9%

          \[\leadsto -0.5 \cdot \frac{c}{b} + -0.375 \cdot \frac{a \cdot {c}^{2}}{{b}^{3}} \]

        Alternative 7: 81.2% accurate, 23.2× 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 31.1%

          \[\frac{\left(-b\right) + \sqrt{b \cdot b - \left(3 \cdot a\right) \cdot c}}{3 \cdot a} \]
        2. Taylor expanded in b around inf 81.4%

          \[\leadsto \color{blue}{-0.5 \cdot \frac{c}{b}} \]
        3. Final simplification81.4%

          \[\leadsto -0.5 \cdot \frac{c}{b} \]

        Alternative 8: 3.2% accurate, 116.0× 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 31.1%

          \[\frac{\left(-b\right) + \sqrt{b \cdot b - \left(3 \cdot a\right) \cdot c}}{3 \cdot a} \]
        2. Step-by-step derivation
          1. Simplified31.1%

            \[\leadsto \color{blue}{\frac{\sqrt{\mathsf{fma}\left(a, c \cdot -3, b \cdot b\right)} - b}{3 \cdot a}} \]
          2. Step-by-step derivation
            1. fma-udef31.1%

              \[\leadsto \frac{\sqrt{\color{blue}{a \cdot \left(c \cdot -3\right) + b \cdot b}} - b}{3 \cdot a} \]
            2. *-commutative31.1%

              \[\leadsto \frac{\sqrt{\color{blue}{\left(c \cdot -3\right) \cdot a} + b \cdot b} - b}{3 \cdot a} \]
            3. associate-*r*31.1%

              \[\leadsto \frac{\sqrt{\color{blue}{c \cdot \left(-3 \cdot a\right)} + b \cdot b} - b}{3 \cdot a} \]
            4. metadata-eval31.1%

              \[\leadsto \frac{\sqrt{c \cdot \left(\color{blue}{\left(-3\right)} \cdot a\right) + b \cdot b} - b}{3 \cdot a} \]
            5. distribute-lft-neg-in31.1%

              \[\leadsto \frac{\sqrt{c \cdot \color{blue}{\left(-3 \cdot a\right)} + b \cdot b} - b}{3 \cdot a} \]
            6. distribute-rgt-neg-in31.1%

              \[\leadsto \frac{\sqrt{\color{blue}{\left(-c \cdot \left(3 \cdot a\right)\right)} + b \cdot b} - b}{3 \cdot a} \]
            7. *-commutative31.1%

              \[\leadsto \frac{\sqrt{\left(-\color{blue}{\left(3 \cdot a\right) \cdot c}\right) + b \cdot b} - b}{3 \cdot a} \]
            8. +-commutative31.1%

              \[\leadsto \frac{\sqrt{\color{blue}{b \cdot b + \left(-\left(3 \cdot a\right) \cdot c\right)}} - b}{3 \cdot a} \]
            9. expm1-log1p-u31.2%

              \[\leadsto \frac{\sqrt{\color{blue}{\mathsf{expm1}\left(\mathsf{log1p}\left(b \cdot b + \left(-\left(3 \cdot a\right) \cdot c\right)\right)\right)}} - b}{3 \cdot a} \]
            10. sub-neg31.2%

              \[\leadsto \frac{\sqrt{\mathsf{expm1}\left(\mathsf{log1p}\left(\color{blue}{b \cdot b - \left(3 \cdot a\right) \cdot c}\right)\right)} - b}{3 \cdot a} \]
            11. expm1-udef25.5%

              \[\leadsto \frac{\sqrt{\color{blue}{e^{\mathsf{log1p}\left(b \cdot b - \left(3 \cdot a\right) \cdot c\right)} - 1}} - b}{3 \cdot a} \]
          3. Applied egg-rr25.5%

            \[\leadsto \frac{\sqrt{\color{blue}{e^{\mathsf{log1p}\left(\mathsf{fma}\left(a, c \cdot -3, {b}^{2}\right)\right)} - 1}} - b}{3 \cdot a} \]
          4. Step-by-step derivation
            1. expm1-def31.2%

              \[\leadsto \frac{\sqrt{\color{blue}{\mathsf{expm1}\left(\mathsf{log1p}\left(\mathsf{fma}\left(a, c \cdot -3, {b}^{2}\right)\right)\right)}} - b}{3 \cdot a} \]
            2. expm1-log1p-u31.1%

              \[\leadsto \frac{\sqrt{\color{blue}{\mathsf{fma}\left(a, c \cdot -3, {b}^{2}\right)}} - b}{3 \cdot a} \]
            3. add-cube-cbrt30.5%

              \[\leadsto \frac{\color{blue}{\left(\sqrt[3]{\sqrt{\mathsf{fma}\left(a, c \cdot -3, {b}^{2}\right)}} \cdot \sqrt[3]{\sqrt{\mathsf{fma}\left(a, c \cdot -3, {b}^{2}\right)}}\right) \cdot \sqrt[3]{\sqrt{\mathsf{fma}\left(a, c \cdot -3, {b}^{2}\right)}}} - b}{3 \cdot a} \]
            4. add-sqr-sqrt30.3%

              \[\leadsto \frac{\left(\sqrt[3]{\sqrt{\mathsf{fma}\left(a, c \cdot -3, {b}^{2}\right)}} \cdot \sqrt[3]{\sqrt{\mathsf{fma}\left(a, c \cdot -3, {b}^{2}\right)}}\right) \cdot \sqrt[3]{\sqrt{\mathsf{fma}\left(a, c \cdot -3, {b}^{2}\right)}} - \color{blue}{\sqrt{b} \cdot \sqrt{b}}}{3 \cdot a} \]
            5. prod-diff30.8%

              \[\leadsto \frac{\color{blue}{\mathsf{fma}\left(\sqrt[3]{\sqrt{\mathsf{fma}\left(a, c \cdot -3, {b}^{2}\right)}} \cdot \sqrt[3]{\sqrt{\mathsf{fma}\left(a, c \cdot -3, {b}^{2}\right)}}, \sqrt[3]{\sqrt{\mathsf{fma}\left(a, c \cdot -3, {b}^{2}\right)}}, -\sqrt{b} \cdot \sqrt{b}\right) + \mathsf{fma}\left(-\sqrt{b}, \sqrt{b}, \sqrt{b} \cdot \sqrt{b}\right)}}{3 \cdot a} \]
          5. Applied egg-rr32.0%

            \[\leadsto \frac{\color{blue}{\left(\sqrt{\mathsf{fma}\left(a, c \cdot -3, {b}^{2}\right)} - b\right) + \mathsf{fma}\left(-\sqrt{b}, \sqrt{b}, b\right)}}{3 \cdot a} \]
          6. Step-by-step derivation
            1. +-commutative32.0%

              \[\leadsto \frac{\color{blue}{\mathsf{fma}\left(-\sqrt{b}, \sqrt{b}, b\right) + \left(\sqrt{\mathsf{fma}\left(a, c \cdot -3, {b}^{2}\right)} - b\right)}}{3 \cdot a} \]
          7. Simplified32.0%

            \[\leadsto \frac{\color{blue}{\mathsf{fma}\left(-\sqrt{b}, \sqrt{b}, b\right) + \left(\sqrt{\mathsf{fma}\left(a, c \cdot -3, {b}^{2}\right)} - b\right)}}{3 \cdot a} \]
          8. Taylor expanded in a around 0 3.2%

            \[\leadsto \color{blue}{0.3333333333333333 \cdot \frac{\left(-1 \cdot b + 2 \cdot b\right) - b}{a}} \]
          9. Step-by-step derivation
            1. div-sub3.2%

              \[\leadsto 0.3333333333333333 \cdot \color{blue}{\left(\frac{-1 \cdot b + 2 \cdot b}{a} - \frac{b}{a}\right)} \]
            2. distribute-rgt-out3.2%

              \[\leadsto 0.3333333333333333 \cdot \left(\frac{\color{blue}{b \cdot \left(-1 + 2\right)}}{a} - \frac{b}{a}\right) \]
            3. metadata-eval3.2%

              \[\leadsto 0.3333333333333333 \cdot \left(\frac{b \cdot \color{blue}{1}}{a} - \frac{b}{a}\right) \]
            4. *-rgt-identity3.2%

              \[\leadsto 0.3333333333333333 \cdot \left(\frac{\color{blue}{b}}{a} - \frac{b}{a}\right) \]
            5. +-inverses3.2%

              \[\leadsto 0.3333333333333333 \cdot \color{blue}{0} \]
            6. metadata-eval3.2%

              \[\leadsto \color{blue}{0} \]
          10. Simplified3.2%

            \[\leadsto \color{blue}{0} \]
          11. Final simplification3.2%

            \[\leadsto 0 \]

          Reproduce

          ?
          herbie shell --seed 2023333 
          (FPCore (a b c)
            :name "Cubic critical, medium range"
            :precision binary64
            :pre (and (and (and (< 1.1102230246251565e-16 a) (< a 9007199254740992.0)) (and (< 1.1102230246251565e-16 b) (< b 9007199254740992.0))) (and (< 1.1102230246251565e-16 c) (< c 9007199254740992.0)))
            (/ (+ (- b) (sqrt (- (* b b) (* (* 3.0 a) c)))) (* 3.0 a)))