\frac{x}{x + 1} - \frac{x + 1}{x - 1}\begin{array}{l}
\mathbf{if}\;x \le -11755.062723959316 \lor \neg \left(x \le 14618.9471916209168\right):\\
\;\;\;\;-\left(\left(\frac{3}{x} + \frac{1}{x \cdot x}\right) + \frac{3}{{x}^{3}}\right)\\
\mathbf{else}:\\
\;\;\;\;\frac{\frac{x}{x + 1} \cdot \frac{x}{x + 1} - \frac{x + 1}{x - 1} \cdot \frac{x + 1}{x - 1}}{\frac{x}{x + 1} + \frac{x + 1}{x - 1}}\\
\end{array}double f(double x) {
double r103425 = x;
double r103426 = 1.0;
double r103427 = r103425 + r103426;
double r103428 = r103425 / r103427;
double r103429 = r103425 - r103426;
double r103430 = r103427 / r103429;
double r103431 = r103428 - r103430;
return r103431;
}
double f(double x) {
double r103432 = x;
double r103433 = -11755.062723959316;
bool r103434 = r103432 <= r103433;
double r103435 = 14618.947191620917;
bool r103436 = r103432 <= r103435;
double r103437 = !r103436;
bool r103438 = r103434 || r103437;
double r103439 = 3.0;
double r103440 = r103439 / r103432;
double r103441 = 1.0;
double r103442 = r103432 * r103432;
double r103443 = r103441 / r103442;
double r103444 = r103440 + r103443;
double r103445 = 3.0;
double r103446 = pow(r103432, r103445);
double r103447 = r103439 / r103446;
double r103448 = r103444 + r103447;
double r103449 = -r103448;
double r103450 = r103432 + r103441;
double r103451 = r103432 / r103450;
double r103452 = r103451 * r103451;
double r103453 = r103432 - r103441;
double r103454 = r103450 / r103453;
double r103455 = r103454 * r103454;
double r103456 = r103452 - r103455;
double r103457 = r103451 + r103454;
double r103458 = r103456 / r103457;
double r103459 = r103438 ? r103449 : r103458;
return r103459;
}



Bits error versus x
Results
if x < -11755.062723959316 or 14618.947191620917 < x Initial program 59.5
Taylor expanded around inf 0.3
Simplified0.0
if -11755.062723959316 < x < 14618.947191620917Initial program 0.1
rmApplied flip--0.1
Final simplification0.1
herbie shell --seed 2020046
(FPCore (x)
:name "Asymptote C"
:precision binary64
(- (/ x (+ x 1)) (/ (+ x 1) (- x 1))))