\frac{x - \sin x}{x - \tan x}\begin{array}{l}
\mathbf{if}\;x \le -1.584526220894006520722996356198564171791 \lor \neg \left(x \le 1.580791957268951719584038073662668466568\right):\\
\;\;\;\;\sqrt{\frac{x - \sin x}{x - \tan x}} \cdot \sqrt{\frac{x - \sin x}{x - \tan x}}\\
\mathbf{else}:\\
\;\;\;\;\frac{9}{40} \cdot {x}^{2} - \left(\log \left(e^{\frac{27}{2800} \cdot {x}^{4}}\right) + \frac{1}{2}\right)\\
\end{array}double f(double x) {
double r10283 = x;
double r10284 = sin(r10283);
double r10285 = r10283 - r10284;
double r10286 = tan(r10283);
double r10287 = r10283 - r10286;
double r10288 = r10285 / r10287;
return r10288;
}
double f(double x) {
double r10289 = x;
double r10290 = -1.5845262208940065;
bool r10291 = r10289 <= r10290;
double r10292 = 1.5807919572689517;
bool r10293 = r10289 <= r10292;
double r10294 = !r10293;
bool r10295 = r10291 || r10294;
double r10296 = sin(r10289);
double r10297 = r10289 - r10296;
double r10298 = tan(r10289);
double r10299 = r10289 - r10298;
double r10300 = r10297 / r10299;
double r10301 = sqrt(r10300);
double r10302 = r10301 * r10301;
double r10303 = 0.225;
double r10304 = 2.0;
double r10305 = pow(r10289, r10304);
double r10306 = r10303 * r10305;
double r10307 = 0.009642857142857142;
double r10308 = 4.0;
double r10309 = pow(r10289, r10308);
double r10310 = r10307 * r10309;
double r10311 = exp(r10310);
double r10312 = log(r10311);
double r10313 = 0.5;
double r10314 = r10312 + r10313;
double r10315 = r10306 - r10314;
double r10316 = r10295 ? r10302 : r10315;
return r10316;
}



Bits error versus x
Results
if x < -1.5845262208940065 or 1.5807919572689517 < x Initial program 0.0
rmApplied add-sqr-sqrt0.0
if -1.5845262208940065 < x < 1.5807919572689517Initial program 63.0
Taylor expanded around 0 0.1
rmApplied add-log-exp0.1
Final simplification0.1
herbie shell --seed 2019353
(FPCore (x)
:name "sintan (problem 3.4.5)"
:precision binary64
(/ (- x (sin x)) (- x (tan x))))