Average Error: 1.0 → 0.0
Time: 3.6s
Precision: 64
\[2 \cdot \cos \left(\frac{2 \cdot \pi}{3} + \frac{\cos^{-1} \left(\frac{-g}{h}\right)}{3}\right)\]
\[2 \cdot \left(\cos \left(\frac{\pi}{3}\right) \cdot \cos \left(\frac{\cos^{-1} \left(\frac{g}{h}\right) - 2 \cdot \pi}{3}\right) + \sin \left(\frac{\pi}{3}\right) \cdot \sin \left(\frac{\cos^{-1} \left(\frac{g}{h}\right) - 2 \cdot \pi}{3}\right)\right)\]

Error

Bits error versus g

Bits error versus h

Derivation

  1. Initial program 1.0

    \[2 \cdot \cos \left(\frac{2 \cdot \pi}{3} + \frac{\cos^{-1} \left(\frac{-g}{h}\right)}{3}\right)\]
  2. Using strategy rm
  3. Applied frac-add1.0

    \[\leadsto 2 \cdot \cos \color{blue}{\left(\frac{\left(2 \cdot \pi\right) \cdot 3 + 3 \cdot \cos^{-1} \left(\frac{-g}{h}\right)}{3 \cdot 3}\right)}\]
  4. Simplified1.0

    \[\leadsto 2 \cdot \cos \left(\frac{\color{blue}{3 \cdot \left(\cos^{-1} \left(\frac{-g}{h}\right) + 2 \cdot \pi\right)}}{3 \cdot 3}\right)\]
  5. Using strategy rm
  6. Applied associate-/r*1.0

    \[\leadsto 2 \cdot \cos \color{blue}{\left(\frac{\frac{3 \cdot \left(\cos^{-1} \left(\frac{-g}{h}\right) + 2 \cdot \pi\right)}{3}}{3}\right)}\]
  7. Simplified1.0

    \[\leadsto 2 \cdot \cos \left(\frac{\color{blue}{\cos^{-1} \left(-1 \cdot \frac{g}{h}\right) + 2 \cdot \pi}}{3}\right)\]
  8. Using strategy rm
  9. Applied mul-1-neg1.0

    \[\leadsto 2 \cdot \cos \left(\frac{\cos^{-1} \color{blue}{\left(-\frac{g}{h}\right)} + 2 \cdot \pi}{3}\right)\]
  10. Applied acos-neg1.0

    \[\leadsto 2 \cdot \cos \left(\frac{\color{blue}{\left(\pi - \cos^{-1} \left(\frac{g}{h}\right)\right)} + 2 \cdot \pi}{3}\right)\]
  11. Applied associate-+l-1.0

    \[\leadsto 2 \cdot \cos \left(\frac{\color{blue}{\pi - \left(\cos^{-1} \left(\frac{g}{h}\right) - 2 \cdot \pi\right)}}{3}\right)\]
  12. Applied div-sub1.0

    \[\leadsto 2 \cdot \cos \color{blue}{\left(\frac{\pi}{3} - \frac{\cos^{-1} \left(\frac{g}{h}\right) - 2 \cdot \pi}{3}\right)}\]
  13. Applied cos-diff0.0

    \[\leadsto 2 \cdot \color{blue}{\left(\cos \left(\frac{\pi}{3}\right) \cdot \cos \left(\frac{\cos^{-1} \left(\frac{g}{h}\right) - 2 \cdot \pi}{3}\right) + \sin \left(\frac{\pi}{3}\right) \cdot \sin \left(\frac{\cos^{-1} \left(\frac{g}{h}\right) - 2 \cdot \pi}{3}\right)\right)}\]
  14. Final simplification0.0

    \[\leadsto 2 \cdot \left(\cos \left(\frac{\pi}{3}\right) \cdot \cos \left(\frac{\cos^{-1} \left(\frac{g}{h}\right) - 2 \cdot \pi}{3}\right) + \sin \left(\frac{\pi}{3}\right) \cdot \sin \left(\frac{\cos^{-1} \left(\frac{g}{h}\right) - 2 \cdot \pi}{3}\right)\right)\]

Reproduce

herbie shell --seed 2020130 
(FPCore (g h)
  :name "2-ancestry mixing, negative discriminant"
  :precision binary64
  (* 2.0 (cos (+ (/ (* 2.0 PI) 3.0) (/ (acos (/ (- g) h)) 3.0)))))