Average Error: 28.6 → 0.5
Time: 38.3s
Precision: 64
Internal Precision: 128
\[\frac{\left(-b\right) + \sqrt{b \cdot b - \left(3 \cdot a\right) \cdot c}}{3 \cdot a}\]
\[\frac{\frac{\frac{1}{3}}{a}}{b + \sqrt{(\left(a \cdot -3\right) \cdot c + \left(b \cdot b\right))_*}} \cdot \frac{c}{\frac{\frac{-1}{3}}{a}}\]

Error

Bits error versus a

Bits error versus b

Bits error versus c

Bits error versus d

Derivation

  1. Initial program 28.6

    \[\frac{\left(-b\right) + \sqrt{b \cdot b - \left(3 \cdot a\right) \cdot c}}{3 \cdot a}\]
  2. Initial simplification28.6

    \[\leadsto \frac{\sqrt{(-3 \cdot \left(c \cdot a\right) + \left(b \cdot b\right))_*} - b}{3 \cdot a}\]
  3. Using strategy rm
  4. Applied flip--28.6

    \[\leadsto \frac{\color{blue}{\frac{\sqrt{(-3 \cdot \left(c \cdot a\right) + \left(b \cdot b\right))_*} \cdot \sqrt{(-3 \cdot \left(c \cdot a\right) + \left(b \cdot b\right))_*} - b \cdot b}{\sqrt{(-3 \cdot \left(c \cdot a\right) + \left(b \cdot b\right))_*} + b}}}{3 \cdot a}\]
  5. Applied associate-/l/28.6

    \[\leadsto \color{blue}{\frac{\sqrt{(-3 \cdot \left(c \cdot a\right) + \left(b \cdot b\right))_*} \cdot \sqrt{(-3 \cdot \left(c \cdot a\right) + \left(b \cdot b\right))_*} - b \cdot b}{\left(3 \cdot a\right) \cdot \left(\sqrt{(-3 \cdot \left(c \cdot a\right) + \left(b \cdot b\right))_*} + b\right)}}\]
  6. Simplified0.6

    \[\leadsto \frac{\color{blue}{\left(a \cdot c\right) \cdot -3}}{\left(3 \cdot a\right) \cdot \left(\sqrt{(-3 \cdot \left(c \cdot a\right) + \left(b \cdot b\right))_*} + b\right)}\]
  7. Using strategy rm
  8. Applied distribute-lft-in0.6

    \[\leadsto \frac{\left(a \cdot c\right) \cdot -3}{\color{blue}{\left(3 \cdot a\right) \cdot \sqrt{(-3 \cdot \left(c \cdot a\right) + \left(b \cdot b\right))_*} + \left(3 \cdot a\right) \cdot b}}\]
  9. Using strategy rm
  10. Applied *-un-lft-identity0.6

    \[\leadsto \frac{\left(a \cdot c\right) \cdot -3}{\color{blue}{1 \cdot \left(\left(3 \cdot a\right) \cdot \sqrt{(-3 \cdot \left(c \cdot a\right) + \left(b \cdot b\right))_*} + \left(3 \cdot a\right) \cdot b\right)}}\]
  11. Applied associate-/r*0.6

    \[\leadsto \color{blue}{\frac{\frac{\left(a \cdot c\right) \cdot -3}{1}}{\left(3 \cdot a\right) \cdot \sqrt{(-3 \cdot \left(c \cdot a\right) + \left(b \cdot b\right))_*} + \left(3 \cdot a\right) \cdot b}}\]
  12. Simplified0.5

    \[\leadsto \frac{\frac{\left(a \cdot c\right) \cdot -3}{1}}{\color{blue}{(\left(3 \cdot a\right) \cdot \left(\sqrt{(-3 \cdot \left(a \cdot c\right) + \left(b \cdot b\right))_*}\right) + \left(3 \cdot \left(b \cdot a\right)\right))_*}}\]
  13. Using strategy rm
  14. Applied *-un-lft-identity0.5

    \[\leadsto \frac{\frac{\left(a \cdot c\right) \cdot -3}{1}}{\color{blue}{1 \cdot (\left(3 \cdot a\right) \cdot \left(\sqrt{(-3 \cdot \left(a \cdot c\right) + \left(b \cdot b\right))_*}\right) + \left(3 \cdot \left(b \cdot a\right)\right))_*}}\]
  15. Applied div-inv0.5

    \[\leadsto \frac{\color{blue}{\left(\left(a \cdot c\right) \cdot -3\right) \cdot \frac{1}{1}}}{1 \cdot (\left(3 \cdot a\right) \cdot \left(\sqrt{(-3 \cdot \left(a \cdot c\right) + \left(b \cdot b\right))_*}\right) + \left(3 \cdot \left(b \cdot a\right)\right))_*}\]
  16. Applied times-frac0.6

    \[\leadsto \color{blue}{\frac{\left(a \cdot c\right) \cdot -3}{1} \cdot \frac{\frac{1}{1}}{(\left(3 \cdot a\right) \cdot \left(\sqrt{(-3 \cdot \left(a \cdot c\right) + \left(b \cdot b\right))_*}\right) + \left(3 \cdot \left(b \cdot a\right)\right))_*}}\]
  17. Simplified0.6

    \[\leadsto \color{blue}{\frac{c}{\frac{\frac{-1}{3}}{a}}} \cdot \frac{\frac{1}{1}}{(\left(3 \cdot a\right) \cdot \left(\sqrt{(-3 \cdot \left(a \cdot c\right) + \left(b \cdot b\right))_*}\right) + \left(3 \cdot \left(b \cdot a\right)\right))_*}\]
  18. Simplified0.5

    \[\leadsto \frac{c}{\frac{\frac{-1}{3}}{a}} \cdot \color{blue}{\frac{\frac{\frac{1}{3}}{a}}{b + \sqrt{(\left(a \cdot -3\right) \cdot c + \left(b \cdot b\right))_*}}}\]
  19. Final simplification0.5

    \[\leadsto \frac{\frac{\frac{1}{3}}{a}}{b + \sqrt{(\left(a \cdot -3\right) \cdot c + \left(b \cdot b\right))_*}} \cdot \frac{c}{\frac{\frac{-1}{3}}{a}}\]

Runtime

Time bar (total: 38.3s)Debug logProfile

herbie shell --seed 2018304 +o rules:numerics
(FPCore (a b c d)
  :name "Cubic critical, narrow range"
  :pre (and (< 1.0536712127723509e-08 a 94906265.62425156) (< 1.0536712127723509e-08 b 94906265.62425156) (< 1.0536712127723509e-08 c 94906265.62425156))
  (/ (+ (- b) (sqrt (- (* b b) (* (* 3 a) c)))) (* 3 a)))