Average Error: 0.5 → 0.6
Time: 33.1s
Precision: 64
Internal Precision: 576
\[\cos^{-1} \left(\frac{1 - 5 \cdot \left(v \cdot v\right)}{v \cdot v - 1}\right)\]
\[(e^{\log_* (1 + \left(\frac{\pi}{2} - \sin^{-1} \left(\frac{1}{\frac{(v \cdot v + -1)_*}{(\left(-5 \cdot v\right) \cdot v + 1)_*}}\right)\right))} - 1)^*\]

Error

Bits error versus v

Derivation

  1. Initial program 0.5

    \[\cos^{-1} \left(\frac{1 - 5 \cdot \left(v \cdot v\right)}{v \cdot v - 1}\right)\]
  2. Initial simplification0.5

    \[\leadsto \cos^{-1} \left(\frac{(\left(-5 \cdot v\right) \cdot v + 1)_*}{(v \cdot v + -1)_*}\right)\]
  3. Using strategy rm
  4. Applied *-un-lft-identity0.5

    \[\leadsto \cos^{-1} \left(\frac{\color{blue}{1 \cdot (\left(-5 \cdot v\right) \cdot v + 1)_*}}{(v \cdot v + -1)_*}\right)\]
  5. Applied associate-/l*0.6

    \[\leadsto \cos^{-1} \color{blue}{\left(\frac{1}{\frac{(v \cdot v + -1)_*}{(\left(-5 \cdot v\right) \cdot v + 1)_*}}\right)}\]
  6. Using strategy rm
  7. Applied acos-asin0.6

    \[\leadsto \color{blue}{\frac{\pi}{2} - \sin^{-1} \left(\frac{1}{\frac{(v \cdot v + -1)_*}{(\left(-5 \cdot v\right) \cdot v + 1)_*}}\right)}\]
  8. Using strategy rm
  9. Applied expm1-log1p-u0.6

    \[\leadsto \color{blue}{(e^{\log_* (1 + \left(\frac{\pi}{2} - \sin^{-1} \left(\frac{1}{\frac{(v \cdot v + -1)_*}{(\left(-5 \cdot v\right) \cdot v + 1)_*}}\right)\right))} - 1)^*}\]
  10. Final simplification0.6

    \[\leadsto (e^{\log_* (1 + \left(\frac{\pi}{2} - \sin^{-1} \left(\frac{1}{\frac{(v \cdot v + -1)_*}{(\left(-5 \cdot v\right) \cdot v + 1)_*}}\right)\right))} - 1)^*\]

Runtime

Time bar (total: 33.1s)Debug logProfile

herbie shell --seed 2018251 +o rules:numerics
(FPCore (v)
  :name "Falkner and Boettcher, Appendix B, 1"
  (acos (/ (- 1 (* 5 (* v v))) (- (* v v) 1))))