Average Error: 32.9 → 32.3
Time: 54.8s
Precision: 64
Internal Precision: 128
\[\left(\frac{1}{x + 1} - \frac{2}{x}\right) + \frac{1}{x - 1}\]
\[{e}^{\left(\log \left(\log \left(1 + \left(\frac{\frac{2}{x}}{x \cdot x} + \frac{2}{{x}^{5}}\right)\right)\right)\right)}\]

Error

Bits error versus x

Try it out

Your Program's Arguments

Results

Enter valid numbers for all inputs

Target

Original32.9
Target41.8
Herbie32.3
\[\frac{2}{x \cdot \left(x \cdot x - 1\right)}\]

Derivation

  1. Initial program 32.9

    \[\left(\frac{1}{x + 1} - \frac{2}{x}\right) + \frac{1}{x - 1}\]
  2. Using strategy rm
  3. Applied add-log-exp32.3

    \[\leadsto \color{blue}{\log \left(e^{\left(\frac{1}{x + 1} - \frac{2}{x}\right) + \frac{1}{x - 1}}\right)}\]
  4. Taylor expanded around -inf 32.3

    \[\leadsto \log \color{blue}{\left(2 \cdot \frac{1}{{x}^{5}} + \left(2 \cdot \frac{1}{{x}^{3}} + 1\right)\right)}\]
  5. Simplified32.3

    \[\leadsto \log \color{blue}{\left(\left(\frac{\frac{2}{x}}{x \cdot x} + \frac{2}{{x}^{5}}\right) + 1\right)}\]
  6. Using strategy rm
  7. Applied add-exp-log32.3

    \[\leadsto \color{blue}{e^{\log \left(\log \left(\left(\frac{\frac{2}{x}}{x \cdot x} + \frac{2}{{x}^{5}}\right) + 1\right)\right)}}\]
  8. Using strategy rm
  9. Applied pow132.3

    \[\leadsto e^{\log \color{blue}{\left({\left(\log \left(\left(\frac{\frac{2}{x}}{x \cdot x} + \frac{2}{{x}^{5}}\right) + 1\right)\right)}^{1}\right)}}\]
  10. Applied log-pow32.3

    \[\leadsto e^{\color{blue}{1 \cdot \log \left(\log \left(\left(\frac{\frac{2}{x}}{x \cdot x} + \frac{2}{{x}^{5}}\right) + 1\right)\right)}}\]
  11. Applied exp-prod32.3

    \[\leadsto \color{blue}{{\left(e^{1}\right)}^{\left(\log \left(\log \left(\left(\frac{\frac{2}{x}}{x \cdot x} + \frac{2}{{x}^{5}}\right) + 1\right)\right)\right)}}\]
  12. Simplified32.3

    \[\leadsto {\color{blue}{e}}^{\left(\log \left(\log \left(\left(\frac{\frac{2}{x}}{x \cdot x} + \frac{2}{{x}^{5}}\right) + 1\right)\right)\right)}\]
  13. Final simplification32.3

    \[\leadsto {e}^{\left(\log \left(\log \left(1 + \left(\frac{\frac{2}{x}}{x \cdot x} + \frac{2}{{x}^{5}}\right)\right)\right)\right)}\]

Runtime

Time bar (total: 54.8s)Debug logProfile

herbie shell --seed 2018255 +o rules:numerics
(FPCore (x)
  :name "3frac (problem 3.3.3)"

  :herbie-target
  (/ 2 (* x (- (* x x) 1)))

  (+ (- (/ 1 (+ x 1)) (/ 2 x)) (/ 1 (- x 1))))