Average Error: 4.4 → 0.7
Time: 10.8s
Precision: 64
\[\sqrt{\frac{e^{2 \cdot x} - 1}{e^{x} - 1}}\]
\[\begin{array}{l} \mathbf{if}\;x \le -7.26854291605878706 \cdot 10^{-16}:\\ \;\;\;\;\sqrt{\frac{e^{2 \cdot x} - 1}{e^{x + x} - 1 \cdot 1}} \cdot \sqrt{e^{x} + 1}\\ \mathbf{else}:\\ \;\;\;\;\frac{{x}^{2}}{\sqrt{2}} \cdot \left(0.25 - \frac{0.125}{2}\right) + \left(\sqrt{2} + 0.5 \cdot \frac{x}{\sqrt{2}}\right)\\ \end{array}\]
\sqrt{\frac{e^{2 \cdot x} - 1}{e^{x} - 1}}
\begin{array}{l}
\mathbf{if}\;x \le -7.26854291605878706 \cdot 10^{-16}:\\
\;\;\;\;\sqrt{\frac{e^{2 \cdot x} - 1}{e^{x + x} - 1 \cdot 1}} \cdot \sqrt{e^{x} + 1}\\

\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 r14797 = 2.0;
        double r14798 = x;
        double r14799 = r14797 * r14798;
        double r14800 = exp(r14799);
        double r14801 = 1.0;
        double r14802 = r14800 - r14801;
        double r14803 = exp(r14798);
        double r14804 = r14803 - r14801;
        double r14805 = r14802 / r14804;
        double r14806 = sqrt(r14805);
        return r14806;
}

double f(double x) {
        double r14807 = x;
        double r14808 = -7.268542916058787e-16;
        bool r14809 = r14807 <= r14808;
        double r14810 = 2.0;
        double r14811 = r14810 * r14807;
        double r14812 = exp(r14811);
        double r14813 = 1.0;
        double r14814 = r14812 - r14813;
        double r14815 = r14807 + r14807;
        double r14816 = exp(r14815);
        double r14817 = r14813 * r14813;
        double r14818 = r14816 - r14817;
        double r14819 = r14814 / r14818;
        double r14820 = sqrt(r14819);
        double r14821 = exp(r14807);
        double r14822 = r14821 + r14813;
        double r14823 = sqrt(r14822);
        double r14824 = r14820 * r14823;
        double r14825 = 2.0;
        double r14826 = pow(r14807, r14825);
        double r14827 = sqrt(r14810);
        double r14828 = r14826 / r14827;
        double r14829 = 0.25;
        double r14830 = 0.125;
        double r14831 = r14830 / r14810;
        double r14832 = r14829 - r14831;
        double r14833 = r14828 * r14832;
        double r14834 = 0.5;
        double r14835 = r14807 / r14827;
        double r14836 = r14834 * r14835;
        double r14837 = r14827 + r14836;
        double r14838 = r14833 + r14837;
        double r14839 = r14809 ? r14824 : r14838;
        return r14839;
}

Error

Bits error versus x

Try it out

Your Program's Arguments

Results

Enter valid numbers for all inputs

Derivation

  1. Split input into 2 regimes
  2. if x < -7.268542916058787e-16

    1. Initial program 0.7

      \[\sqrt{\frac{e^{2 \cdot x} - 1}{e^{x} - 1}}\]
    2. Using strategy rm
    3. Applied flip--0.5

      \[\leadsto \sqrt{\frac{e^{2 \cdot x} - 1}{\color{blue}{\frac{e^{x} \cdot e^{x} - 1 \cdot 1}{e^{x} + 1}}}}\]
    4. Applied associate-/r/0.5

      \[\leadsto \sqrt{\color{blue}{\frac{e^{2 \cdot x} - 1}{e^{x} \cdot e^{x} - 1 \cdot 1} \cdot \left(e^{x} + 1\right)}}\]
    5. Applied sqrt-prod0.5

      \[\leadsto \color{blue}{\sqrt{\frac{e^{2 \cdot x} - 1}{e^{x} \cdot e^{x} - 1 \cdot 1}} \cdot \sqrt{e^{x} + 1}}\]
    6. Simplified0.0

      \[\leadsto \color{blue}{\sqrt{\frac{e^{2 \cdot x} - 1}{e^{x + x} - 1 \cdot 1}}} \cdot \sqrt{e^{x} + 1}\]

    if -7.268542916058787e-16 < x

    1. Initial program 37.3

      \[\sqrt{\frac{e^{2 \cdot x} - 1}{e^{x} - 1}}\]
    2. Taylor expanded around 0 7.3

      \[\leadsto \color{blue}{\left(0.25 \cdot \frac{{x}^{2}}{\sqrt{2}} + \left(\sqrt{2} + 0.5 \cdot \frac{x}{\sqrt{2}}\right)\right) - 0.125 \cdot \frac{{x}^{2}}{{\left(\sqrt{2}\right)}^{3}}}\]
    3. Simplified7.3

      \[\leadsto \color{blue}{\frac{{x}^{2}}{\sqrt{2}} \cdot \left(0.25 - \frac{0.125}{2}\right) + \left(\sqrt{2} + 0.5 \cdot \frac{x}{\sqrt{2}}\right)}\]
  3. Recombined 2 regimes into one program.
  4. Final simplification0.7

    \[\leadsto \begin{array}{l} \mathbf{if}\;x \le -7.26854291605878706 \cdot 10^{-16}:\\ \;\;\;\;\sqrt{\frac{e^{2 \cdot x} - 1}{e^{x + x} - 1 \cdot 1}} \cdot \sqrt{e^{x} + 1}\\ \mathbf{else}:\\ \;\;\;\;\frac{{x}^{2}}{\sqrt{2}} \cdot \left(0.25 - \frac{0.125}{2}\right) + \left(\sqrt{2} + 0.5 \cdot \frac{x}{\sqrt{2}}\right)\\ \end{array}\]

Reproduce

herbie shell --seed 2020046 
(FPCore (x)
  :name "sqrtexp (problem 3.4.4)"
  :precision binary64
  (sqrt (/ (- (exp (* 2 x)) 1) (- (exp x) 1))))