\sqrt{\frac{e^{2 \cdot x} - 1}{e^{x} - 1}}\begin{array}{l}
\mathbf{if}\;x \le -2.367867422063156052558161035470618571708 \cdot 10^{-5}:\\
\;\;\;\;\sqrt{\frac{e^{2 \cdot x} - 1}{e^{x + x} - 1 \cdot 1} \cdot \left(e^{x} + 1\right)}\\
\mathbf{else}:\\
\;\;\;\;\frac{{x}^{2}}{\sqrt{2}} \cdot \left(0.25 - \frac{0.125}{2}\right) + \left(\sqrt{2} + 0.5 \cdot \frac{x}{\sqrt{2}}\right)\\
\end{array}double f(double x) {
double r24071 = 2.0;
double r24072 = x;
double r24073 = r24071 * r24072;
double r24074 = exp(r24073);
double r24075 = 1.0;
double r24076 = r24074 - r24075;
double r24077 = exp(r24072);
double r24078 = r24077 - r24075;
double r24079 = r24076 / r24078;
double r24080 = sqrt(r24079);
return r24080;
}
double f(double x) {
double r24081 = x;
double r24082 = -2.367867422063156e-05;
bool r24083 = r24081 <= r24082;
double r24084 = 2.0;
double r24085 = r24084 * r24081;
double r24086 = exp(r24085);
double r24087 = 1.0;
double r24088 = r24086 - r24087;
double r24089 = r24081 + r24081;
double r24090 = exp(r24089);
double r24091 = r24087 * r24087;
double r24092 = r24090 - r24091;
double r24093 = r24088 / r24092;
double r24094 = exp(r24081);
double r24095 = r24094 + r24087;
double r24096 = r24093 * r24095;
double r24097 = sqrt(r24096);
double r24098 = 2.0;
double r24099 = pow(r24081, r24098);
double r24100 = sqrt(r24084);
double r24101 = r24099 / r24100;
double r24102 = 0.25;
double r24103 = 0.125;
double r24104 = r24103 / r24084;
double r24105 = r24102 - r24104;
double r24106 = r24101 * r24105;
double r24107 = 0.5;
double r24108 = r24081 / r24100;
double r24109 = r24107 * r24108;
double r24110 = r24100 + r24109;
double r24111 = r24106 + r24110;
double r24112 = r24083 ? r24097 : r24111;
return r24112;
}



Bits error versus x
Results
if x < -2.367867422063156e-05Initial program 0.1
rmApplied flip--0.0
Applied associate-/r/0.0
Simplified0.0
if -2.367867422063156e-05 < x Initial program 34.6
Taylor expanded around 0 5.7
Simplified5.6
Final simplification0.7
herbie shell --seed 2019326
(FPCore (x)
:name "sqrtexp (problem 3.4.4)"
:precision binary64
(sqrt (/ (- (exp (* 2 x)) 1) (- (exp x) 1))))