Average Error: 30.6 → 0.3
Time: 44.6s
Precision: 64
Internal precision: 2432
\[\frac{1 - \cos x}{x \cdot x}\]
\[\frac{\sin x}{x} \cdot \frac{\frac{\sin x}{1 + \cos x}}{x}\]

Error

Bits error versus x

Derivation

  1. Initial program 30.6

    \[\frac{1 - \cos x}{x \cdot x}\]
  2. Using strategy rm
  3. Applied flip-- 30.7

    \[\leadsto \frac{\color{blue}{\frac{1 \cdot 1 - \cos x \cdot \cos x}{1 + \cos x}}}{x \cdot x}\]
  4. Applied simplify 15.3

    \[\leadsto \frac{\frac{\color{blue}{\sin x \cdot \sin x}}{1 + \cos x}}{x \cdot x}\]
  5. Using strategy rm
  6. Applied *-un-lft-identity 15.3

    \[\leadsto \frac{\frac{\sin x \cdot \sin x}{\color{blue}{1 \cdot \left(1 + \cos x\right)}}}{x \cdot x}\]
  7. Applied times-frac 15.3

    \[\leadsto \frac{\color{blue}{\frac{\sin x}{1} \cdot \frac{\sin x}{1 + \cos x}}}{x \cdot x}\]
  8. Applied times-frac 0.3

    \[\leadsto \color{blue}{\frac{\frac{\sin x}{1}}{x} \cdot \frac{\frac{\sin x}{1 + \cos x}}{x}}\]
  9. Applied simplify 0.3

    \[\leadsto \color{blue}{\frac{\sin x}{x}} \cdot \frac{\frac{\sin x}{1 + \cos x}}{x}\]
  10. Removed slow pow expressions

Runtime

Time bar (total: 44.6s) Debug logProfile

Please include this information when filing a bug report:

herbie shell --seed '#(1068028399 4028058041 2917032441 2563479541 765645300 1132738916)'
(FPCore (x)
  :name "cos2 (problem 3.4.1)"
  (/ (- 1 (cos x)) (* x x)))