\frac{x - \sin x}{x - \tan x}\begin{array}{l}
\mathbf{if}\;x \le -2.4354142091382851 \lor \neg \left(x \le 2.4300372653342581\right):\\
\;\;\;\;\left(\frac{\sin x}{x \cdot \cos x} + \left(\frac{{\left(\sin x\right)}^{2}}{{x}^{2} \cdot {\left(\cos x\right)}^{2}} + 1\right)\right) - \left(\frac{\sin x}{x} + \frac{{\left(\sin x\right)}^{2}}{{x}^{2} \cdot \cos 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 r11242 = x;
double r11243 = sin(r11242);
double r11244 = r11242 - r11243;
double r11245 = tan(r11242);
double r11246 = r11242 - r11245;
double r11247 = r11244 / r11246;
return r11247;
}
double f(double x) {
double r11248 = x;
double r11249 = -2.435414209138285;
bool r11250 = r11248 <= r11249;
double r11251 = 2.430037265334258;
bool r11252 = r11248 <= r11251;
double r11253 = !r11252;
bool r11254 = r11250 || r11253;
double r11255 = sin(r11248);
double r11256 = cos(r11248);
double r11257 = r11248 * r11256;
double r11258 = r11255 / r11257;
double r11259 = 2.0;
double r11260 = pow(r11255, r11259);
double r11261 = pow(r11248, r11259);
double r11262 = pow(r11256, r11259);
double r11263 = r11261 * r11262;
double r11264 = r11260 / r11263;
double r11265 = 1.0;
double r11266 = r11264 + r11265;
double r11267 = r11258 + r11266;
double r11268 = r11255 / r11248;
double r11269 = r11261 * r11256;
double r11270 = r11260 / r11269;
double r11271 = r11268 + r11270;
double r11272 = r11267 - r11271;
double r11273 = 0.225;
double r11274 = r11273 * r11261;
double r11275 = 0.009642857142857142;
double r11276 = 4.0;
double r11277 = pow(r11248, r11276);
double r11278 = r11275 * r11277;
double r11279 = r11274 - r11278;
double r11280 = 0.5;
double r11281 = r11279 - r11280;
double r11282 = r11254 ? r11272 : r11281;
return r11282;
}



Bits error versus x
Results
if x < -2.435414209138285 or 2.430037265334258 < x Initial program 0.0
Taylor expanded around inf 0.4
if -2.435414209138285 < x < 2.430037265334258Initial program 62.8
Taylor expanded around 0 0.2
rmApplied associate--r+0.2
Final simplification0.3
herbie shell --seed 2020024
(FPCore (x)
:name "sintan (problem 3.4.5)"
:precision binary64
(/ (- x (sin x)) (- x (tan x))))