\sqrt{\frac{e^{2 \cdot x} - 1}{e^{x} - 1}}
\mathsf{hypot}\left(1, \mathsf{expm1}\left(\mathsf{log1p}\left({e}^{\left(\frac{x}{2}\right)}\right)\right)\right)
(FPCore (x) :precision binary64 (sqrt (/ (- (exp (* 2.0 x)) 1.0) (- (exp x) 1.0))))
(FPCore (x) :precision binary64 (hypot 1.0 (expm1 (log1p (pow E (/ x 2.0))))))
double code(double x) {
return sqrt((exp(2.0 * x) - 1.0) / (exp(x) - 1.0));
}
double code(double x) {
return hypot(1.0, expm1(log1p(pow(((double) M_E), (x / 2.0)))));
}



Bits error versus x
Results
Initial program 40.9
Simplified0.0
Applied add-sqr-sqrt_binary640.0
Applied hypot-1-def_binary640.0
Applied *-un-lft-identity_binary640.0
Applied exp-prod_binary640.0
Applied sqrt-pow1_binary640.0
Applied expm1-log1p-u_binary640.0
Final simplification0.0
herbie shell --seed 2022121
(FPCore (x)
:name "sqrtexp (problem 3.4.4)"
:precision binary64
(sqrt (/ (- (exp (* 2.0 x)) 1.0) (- (exp x) 1.0))))