Average Error: 33.6 → 33.7
Time: 15.5s
Precision: 64
Internal Precision: 3392
\[\frac{\left(-b\right) + \sqrt{b \cdot b - \left(3 \cdot a\right) \cdot c}}{3 \cdot a}\]
\[\frac{\sqrt{b \cdot b - \left(\sqrt[3]{\left(3 \cdot a\right) \cdot c} \cdot \sqrt[3]{\left(3 \cdot a\right) \cdot c}\right) \cdot \left(\sqrt[3]{3 \cdot a} \cdot \sqrt[3]{c}\right)} + \left(-b\right)}{3 \cdot a}\]

Error

Bits error versus a

Bits error versus b

Bits error versus c

Bits error versus d

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Your Program's Arguments

Results

Enter valid numbers for all inputs

Derivation

  1. Initial program 33.6

    \[\frac{\left(-b\right) + \sqrt{b \cdot b - \left(3 \cdot a\right) \cdot c}}{3 \cdot a}\]
  2. Using strategy rm
  3. Applied add-cube-cbrt33.7

    \[\leadsto \frac{\left(-b\right) + \sqrt{b \cdot b - \color{blue}{\left(\sqrt[3]{\left(3 \cdot a\right) \cdot c} \cdot \sqrt[3]{\left(3 \cdot a\right) \cdot c}\right) \cdot \sqrt[3]{\left(3 \cdot a\right) \cdot c}}}}{3 \cdot a}\]
  4. Using strategy rm
  5. Applied cbrt-prod33.7

    \[\leadsto \frac{\left(-b\right) + \sqrt{b \cdot b - \left(\sqrt[3]{\left(3 \cdot a\right) \cdot c} \cdot \sqrt[3]{\left(3 \cdot a\right) \cdot c}\right) \cdot \color{blue}{\left(\sqrt[3]{3 \cdot a} \cdot \sqrt[3]{c}\right)}}}{3 \cdot a}\]
  6. Final simplification33.7

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

Runtime

Time bar (total: 15.5s)Debug logProfile

herbie shell --seed 2018248 
(FPCore (a b c d)
  :name "Cubic critical"
  (/ (+ (- b) (sqrt (- (* b b) (* (* 3 a) c)))) (* 3 a)))