\frac{x - \sin x}{x - \tan x}\begin{array}{l}
\mathbf{if}\;x \le -0.0282266077727037941 \lor \neg \left(x \le 0.025407348733278587\right):\\
\;\;\;\;\log \left(e^{\frac{x - \sin x}{x - \tan x}}\right)\\
\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 r11488 = x;
double r11489 = sin(r11488);
double r11490 = r11488 - r11489;
double r11491 = tan(r11488);
double r11492 = r11488 - r11491;
double r11493 = r11490 / r11492;
return r11493;
}
double f(double x) {
double r11494 = x;
double r11495 = -0.028226607772703794;
bool r11496 = r11494 <= r11495;
double r11497 = 0.025407348733278587;
bool r11498 = r11494 <= r11497;
double r11499 = !r11498;
bool r11500 = r11496 || r11499;
double r11501 = sin(r11494);
double r11502 = r11494 - r11501;
double r11503 = tan(r11494);
double r11504 = r11494 - r11503;
double r11505 = r11502 / r11504;
double r11506 = exp(r11505);
double r11507 = log(r11506);
double r11508 = 0.225;
double r11509 = 2.0;
double r11510 = pow(r11494, r11509);
double r11511 = r11508 * r11510;
double r11512 = 0.009642857142857142;
double r11513 = 4.0;
double r11514 = pow(r11494, r11513);
double r11515 = r11512 * r11514;
double r11516 = r11511 - r11515;
double r11517 = 0.5;
double r11518 = r11516 - r11517;
double r11519 = r11500 ? r11507 : r11518;
return r11519;
}



Bits error versus x
Results
if x < -0.028226607772703794 or 0.025407348733278587 < x Initial program 0.0
rmApplied add-log-exp0.0
if -0.028226607772703794 < x < 0.025407348733278587Initial program 63.3
Taylor expanded around 0 0.0
rmApplied associate--r+0.0
Final simplification0.0
herbie shell --seed 2020018
(FPCore (x)
:name "sintan (problem 3.4.5)"
:precision binary64
(/ (- x (sin x)) (- x (tan x))))