\frac{x - \sin x}{x - \tan x}\begin{array}{l}
\mathbf{if}\;x \le -0.0289521418860340281 \lor \neg \left(x \le 0.0280055017289512036\right):\\
\;\;\;\;\left(\sqrt[3]{\frac{x - \sin x}{x - \tan x}} \cdot \sqrt[3]{\frac{x - \sin x}{x - \tan x}}\right) \cdot \sqrt[3]{\frac{x - \sin x}{x - \tan x}}\\
\mathbf{else}:\\
\;\;\;\;\left(\frac{9}{40} \cdot {x}^{2} - \frac{27}{2800} \cdot {x}^{4}\right) - \frac{1}{2}\\
\end{array}double f(double x) {
double r10552 = x;
double r10553 = sin(r10552);
double r10554 = r10552 - r10553;
double r10555 = tan(r10552);
double r10556 = r10552 - r10555;
double r10557 = r10554 / r10556;
return r10557;
}
double f(double x) {
double r10558 = x;
double r10559 = -0.028952141886034028;
bool r10560 = r10558 <= r10559;
double r10561 = 0.028005501728951204;
bool r10562 = r10558 <= r10561;
double r10563 = !r10562;
bool r10564 = r10560 || r10563;
double r10565 = sin(r10558);
double r10566 = r10558 - r10565;
double r10567 = tan(r10558);
double r10568 = r10558 - r10567;
double r10569 = r10566 / r10568;
double r10570 = cbrt(r10569);
double r10571 = r10570 * r10570;
double r10572 = r10571 * r10570;
double r10573 = 0.225;
double r10574 = 2.0;
double r10575 = pow(r10558, r10574);
double r10576 = r10573 * r10575;
double r10577 = 0.009642857142857142;
double r10578 = 4.0;
double r10579 = pow(r10558, r10578);
double r10580 = r10577 * r10579;
double r10581 = r10576 - r10580;
double r10582 = 0.5;
double r10583 = r10581 - r10582;
double r10584 = r10564 ? r10572 : r10583;
return r10584;
}



Bits error versus x
Results
if x < -0.028952141886034028 or 0.028005501728951204 < x Initial program 0.1
rmApplied add-cube-cbrt0.1
if -0.028952141886034028 < x < 0.028005501728951204Initial program 63.2
Taylor expanded around 0 0.0
rmApplied associate--r+0.0
Final simplification0.1
herbie shell --seed 2020089
(FPCore (x)
:name "sintan (problem 3.4.5)"
:precision binary64
(/ (- x (sin x)) (- x (tan x))))