\frac{x - \sin x}{x - \tan x}\begin{array}{l}
\mathbf{if}\;x \le -0.02679764477988002754904606206309836125001:\\
\;\;\;\;\frac{\frac{\mathsf{fma}\left(x, \frac{x}{x - \tan x}, \frac{-{\left(\sin x\right)}^{2}}{x - \tan x}\right)}{x - \tan x}}{\frac{x}{x - \tan x} + \frac{\sin x}{\frac{x \cdot x - \tan x \cdot \tan x}{x + \tan x}}}\\
\mathbf{elif}\;x \le 0.02671164277294657204975258935064630350098:\\
\;\;\;\;\mathsf{fma}\left(\frac{9}{40}, {x}^{2}, -\mathsf{fma}\left(\frac{27}{2800}, {x}^{4}, \frac{1}{2}\right)\right)\\
\mathbf{else}:\\
\;\;\;\;\frac{x}{x - \tan x} - \frac{\sin x}{x - \tan x}\\
\end{array}double f(double x) {
double r22032 = x;
double r22033 = sin(r22032);
double r22034 = r22032 - r22033;
double r22035 = tan(r22032);
double r22036 = r22032 - r22035;
double r22037 = r22034 / r22036;
return r22037;
}
double f(double x) {
double r22038 = x;
double r22039 = -0.026797644779880028;
bool r22040 = r22038 <= r22039;
double r22041 = tan(r22038);
double r22042 = r22038 - r22041;
double r22043 = r22038 / r22042;
double r22044 = sin(r22038);
double r22045 = 2.0;
double r22046 = pow(r22044, r22045);
double r22047 = -r22046;
double r22048 = r22047 / r22042;
double r22049 = fma(r22038, r22043, r22048);
double r22050 = r22049 / r22042;
double r22051 = r22038 * r22038;
double r22052 = r22041 * r22041;
double r22053 = r22051 - r22052;
double r22054 = r22038 + r22041;
double r22055 = r22053 / r22054;
double r22056 = r22044 / r22055;
double r22057 = r22043 + r22056;
double r22058 = r22050 / r22057;
double r22059 = 0.026711642772946572;
bool r22060 = r22038 <= r22059;
double r22061 = 0.225;
double r22062 = pow(r22038, r22045);
double r22063 = 0.009642857142857142;
double r22064 = 4.0;
double r22065 = pow(r22038, r22064);
double r22066 = 0.5;
double r22067 = fma(r22063, r22065, r22066);
double r22068 = -r22067;
double r22069 = fma(r22061, r22062, r22068);
double r22070 = r22044 / r22042;
double r22071 = r22043 - r22070;
double r22072 = r22060 ? r22069 : r22071;
double r22073 = r22040 ? r22058 : r22072;
return r22073;
}



Bits error versus x
if x < -0.026797644779880028Initial program 0.0
rmApplied div-sub0.1
rmApplied flip--0.1
rmApplied associate-*r/0.1
Applied associate-*r/0.1
Applied sub-div0.1
Simplified0.0
rmApplied flip--0.0
if -0.026797644779880028 < x < 0.026711642772946572Initial program 63.3
Taylor expanded around 0 0.0
Simplified0.0
if 0.026711642772946572 < x Initial program 0.0
rmApplied div-sub0.1
Final simplification0.0
herbie shell --seed 2020001 +o rules:numerics
(FPCore (x)
:name "sintan (problem 3.4.5)"
:precision binary64
(/ (- x (sin x)) (- x (tan x))))