Average Error: 14.7 → 0.1
Time: 2.8s
Precision: binary64
\[\frac{1}{x + 1} - \frac{1}{x - 1} \]
↓
\[\frac{\frac{-2}{x + 1}}{x - 1} \]
\frac{1}{x + 1} - \frac{1}{x - 1}
↓
\frac{\frac{-2}{x + 1}}{x - 1}

(FPCore (x) :precision binary64 (- (/ 1.0 (+ x 1.0)) (/ 1.0 (- x 1.0))))
↓
(FPCore (x) :precision binary64 (/ (/ -2.0 (+ x 1.0)) (- x 1.0)))
double code(double x) {
	return (1.0 / (x + 1.0)) - (1.0 / (x - 1.0));
}
↓
double code(double x) {
	return (-2.0 / (x + 1.0)) / (x - 1.0);
}

Error

Bits error versus x

Try it out

Your Program's Arguments

Results

Enter valid numbers for all inputs

Derivation

  1. Initial program 14.7

    \[\frac{1}{x + 1} - \frac{1}{x - 1} \]
  2. Using strategy rm

  3. Applied frac-sub_binary6414.0

    \[\leadsto \color{blue}{\frac{1 \cdot \left(x - 1\right) - \left(x + 1\right) \cdot 1}{\left(x + 1\right) \cdot \left(x - 1\right)}} \]

  4. Simplified0.4

    \[\leadsto \frac{\color{blue}{-2}}{\left(x + 1\right) \cdot \left(x - 1\right)} \]

  5. Simplified0.4

    \[\leadsto \frac{-2}{\color{blue}{x \cdot x + -1}} \]
  6. Using strategy rm

  7. Applied difference-of-sqr--1_binary640.4

    \[\leadsto \frac{-2}{\color{blue}{\left(x + 1\right) \cdot \left(x - 1\right)}} \]

  8. Applied associate-/r*_binary640.1

    \[\leadsto \color{blue}{\frac{\frac{-2}{x + 1}}{x - 1}} \]

  9. Final simplification0.1

    \[\leadsto \frac{\frac{-2}{x + 1}}{x - 1} \]

Reproduce

herbie shell --seed 2021196 
(FPCore (x)
  :name "Asymptote A"
  :precision binary64
  (- (/ 1.0 (+ x 1.0)) (/ 1.0 (- x 1.0))))