\sqrt{\frac{e^{2 \cdot x} - 1}{e^{x} - 1}}\begin{array}{l}
\mathbf{if}\;x \le -2.43227249335068785122152625098948530713 \cdot 10^{-8}:\\
\;\;\;\;\sqrt{\frac{\left(\sqrt{1} + \sqrt{e^{2 \cdot x}}\right) \cdot \left(\sqrt{e^{2 \cdot x}} - \sqrt{1}\right)}{e^{x} - 1}}\\
\mathbf{else}:\\
\;\;\;\;\left(\left(0.25 - \frac{0.125}{2}\right) \cdot \frac{x}{\frac{\sqrt{2}}{x}} + \frac{0.5}{\frac{\sqrt{2}}{x}}\right) + \sqrt{2}\\
\end{array}double f(double x) {
double r2291547 = 2.0;
double r2291548 = x;
double r2291549 = r2291547 * r2291548;
double r2291550 = exp(r2291549);
double r2291551 = 1.0;
double r2291552 = r2291550 - r2291551;
double r2291553 = exp(r2291548);
double r2291554 = r2291553 - r2291551;
double r2291555 = r2291552 / r2291554;
double r2291556 = sqrt(r2291555);
return r2291556;
}
double f(double x) {
double r2291557 = x;
double r2291558 = -2.432272493350688e-08;
bool r2291559 = r2291557 <= r2291558;
double r2291560 = 1.0;
double r2291561 = sqrt(r2291560);
double r2291562 = 2.0;
double r2291563 = r2291562 * r2291557;
double r2291564 = exp(r2291563);
double r2291565 = sqrt(r2291564);
double r2291566 = r2291561 + r2291565;
double r2291567 = r2291565 - r2291561;
double r2291568 = r2291566 * r2291567;
double r2291569 = exp(r2291557);
double r2291570 = r2291569 - r2291560;
double r2291571 = r2291568 / r2291570;
double r2291572 = sqrt(r2291571);
double r2291573 = 0.25;
double r2291574 = 0.125;
double r2291575 = r2291574 / r2291562;
double r2291576 = r2291573 - r2291575;
double r2291577 = sqrt(r2291562);
double r2291578 = r2291577 / r2291557;
double r2291579 = r2291557 / r2291578;
double r2291580 = r2291576 * r2291579;
double r2291581 = 0.5;
double r2291582 = r2291581 / r2291578;
double r2291583 = r2291580 + r2291582;
double r2291584 = r2291583 + r2291577;
double r2291585 = r2291559 ? r2291572 : r2291584;
return r2291585;
}



Bits error versus x
Results
if x < -2.432272493350688e-08Initial program 0.2
rmApplied add-sqr-sqrt0.2
Applied add-sqr-sqrt0.2
Applied difference-of-squares0.0
if -2.432272493350688e-08 < x Initial program 35.6
Taylor expanded around 0 6.0
Simplified6.0
Final simplification0.7
herbie shell --seed 2019171
(FPCore (x)
:name "sqrtexp (problem 3.4.4)"
(sqrt (/ (- (exp (* 2.0 x)) 1.0) (- (exp x) 1.0))))