\frac{1 - \tan x \cdot \tan x}{1 + \tan x \cdot \tan x}\frac{\left(1 - \frac{\sin x \cdot \tan x}{\cos x}\right) \cdot \left(1 + \tan x \cdot \tan x\right)}{1 \cdot \left(1 + \tan x \cdot \tan x\right) + \left(\tan x \cdot \tan x\right) \cdot \left(1 + \tan x \cdot \tan x\right)}double f(double x) {
double r1042825 = 1.0;
double r1042826 = x;
double r1042827 = tan(r1042826);
double r1042828 = r1042827 * r1042827;
double r1042829 = r1042825 - r1042828;
double r1042830 = r1042825 + r1042828;
double r1042831 = r1042829 / r1042830;
return r1042831;
}
double f(double x) {
double r1042832 = 1.0;
double r1042833 = x;
double r1042834 = sin(r1042833);
double r1042835 = tan(r1042833);
double r1042836 = r1042834 * r1042835;
double r1042837 = cos(r1042833);
double r1042838 = r1042836 / r1042837;
double r1042839 = r1042832 - r1042838;
double r1042840 = r1042835 * r1042835;
double r1042841 = r1042832 + r1042840;
double r1042842 = r1042839 * r1042841;
double r1042843 = r1042832 * r1042841;
double r1042844 = r1042840 * r1042841;
double r1042845 = r1042843 + r1042844;
double r1042846 = r1042842 / r1042845;
return r1042846;
}



Bits error versus x
Results
Initial program 0.3
rmApplied div-inv0.4
rmApplied flip--0.4
Applied frac-times0.4
Simplified0.4
rmApplied tan-quot0.4
Applied associate-*l/0.4
rmApplied distribute-rgt-in0.4
Final simplification0.4
herbie shell --seed 2019174
(FPCore (x)
:name "Trigonometry B"
(/ (- 1.0 (* (tan x) (tan x))) (+ 1.0 (* (tan x) (tan x)))))