Average Error: 16.6 → 0.0
Time: 9.3s
Precision: binary64
\[\frac{x - \sin x}{x - \tan x}\]
↓
\[\begin{array}{l} \mathbf{if}\;x \le -0.038023035235741562:\\ \;\;\;\;\frac{x}{x - \tan x} - \left(\sqrt[3]{\frac{\sin x}{x - \tan x}} \cdot \sqrt[3]{\frac{\sin x}{x - \tan x}}\right) \cdot \sqrt[3]{\frac{\sin x}{x - \tan x}}\\ \mathbf{elif}\;x \le 0.032664684127771418:\\ \;\;\;\;\frac{9}{40} \cdot {x}^{2} - \left(\frac{27}{2800} \cdot {x}^{4} + \frac{1}{2}\right)\\ \mathbf{else}:\\ \;\;\;\;\frac{x}{x - \tan x} - \sin x \cdot \frac{1}{x - \tan x}\\ \end{array}\]
\frac{x - \sin x}{x - \tan x}
↓
\begin{array}{l}
\mathbf{if}\;x \le -0.038023035235741562:\\
\;\;\;\;\frac{x}{x - \tan x} - \left(\sqrt[3]{\frac{\sin x}{x - \tan x}} \cdot \sqrt[3]{\frac{\sin x}{x - \tan x}}\right) \cdot \sqrt[3]{\frac{\sin x}{x - \tan x}}\\

\mathbf{elif}\;x \le 0.032664684127771418:\\
\;\;\;\;\frac{9}{40} \cdot {x}^{2} - \left(\frac{27}{2800} \cdot {x}^{4} + \frac{1}{2}\right)\\

\mathbf{else}:\\
\;\;\;\;\frac{x}{x - \tan x} - \sin x \cdot \frac{1}{x - \tan x}\\

\end{array}
double code(double x) {
	return ((double) (((double) (x - ((double) sin(x)))) / ((double) (x - ((double) tan(x))))));
}
↓
double code(double x) {
	double VAR;
	if ((x <= -0.03802303523574156)) {
		VAR = ((double) (((double) (x / ((double) (x - ((double) tan(x)))))) - ((double) (((double) (((double) cbrt(((double) (((double) sin(x)) / ((double) (x - ((double) tan(x)))))))) * ((double) cbrt(((double) (((double) sin(x)) / ((double) (x - ((double) tan(x)))))))))) * ((double) cbrt(((double) (((double) sin(x)) / ((double) (x - ((double) tan(x))))))))))));
	} else {
		double VAR_1;
		if ((x <= 0.03266468412777142)) {
			VAR_1 = ((double) (((double) (0.225 * ((double) pow(x, 2.0)))) - ((double) (((double) (0.009642857142857142 * ((double) pow(x, 4.0)))) + 0.5))));
		} else {
			VAR_1 = ((double) (((double) (x / ((double) (x - ((double) tan(x)))))) - ((double) (((double) sin(x)) * ((double) (1.0 / ((double) (x - ((double) tan(x))))))))));
		}
		VAR = VAR_1;
	}
	return VAR;
}

Error

Bits error versus x

Try it out

Your Program's Arguments

Results

Enter valid numbers for all inputs

Derivation

  1. Split input into 3 regimes

  2. if x < -0.038023035235741562

    1. Initial program 0.0

      \[\frac{x - \sin x}{x - \tan x}\]
    2. Using strategy rm

    3. Applied div-sub0.0

      \[\leadsto \color{blue}{\frac{x}{x - \tan x} - \frac{\sin x}{x - \tan x}}\]
    4. Using strategy rm

    5. Applied add-cube-cbrt0.0

      \[\leadsto \frac{x}{x - \tan x} - \color{blue}{\left(\sqrt[3]{\frac{\sin x}{x - \tan x}} \cdot \sqrt[3]{\frac{\sin x}{x - \tan x}}\right) \cdot \sqrt[3]{\frac{\sin x}{x - \tan x}}}\]

    if -0.038023035235741562 < x < 0.032664684127771418

    1. Initial program 62.8

      \[\frac{x - \sin x}{x - \tan x}\]

    2. Taylor expanded around 0 0.0

      \[\leadsto \color{blue}{\frac{9}{40} \cdot {x}^{2} - \left(\frac{27}{2800} \cdot {x}^{4} + \frac{1}{2}\right)}\]

    if 0.032664684127771418 < x

    1. Initial program 0.1

      \[\frac{x - \sin x}{x - \tan x}\]
    2. Using strategy rm

    3. Applied div-sub0.1

      \[\leadsto \color{blue}{\frac{x}{x - \tan x} - \frac{\sin x}{x - \tan x}}\]
    4. Using strategy rm

    5. Applied div-inv0.1

      \[\leadsto \frac{x}{x - \tan x} - \color{blue}{\sin x \cdot \frac{1}{x - \tan x}}\]
  3. Recombined 3 regimes into one program.

  4. Final simplification0.0

    \[\leadsto \begin{array}{l} \mathbf{if}\;x \le -0.038023035235741562:\\ \;\;\;\;\frac{x}{x - \tan x} - \left(\sqrt[3]{\frac{\sin x}{x - \tan x}} \cdot \sqrt[3]{\frac{\sin x}{x - \tan x}}\right) \cdot \sqrt[3]{\frac{\sin x}{x - \tan x}}\\ \mathbf{elif}\;x \le 0.032664684127771418:\\ \;\;\;\;\frac{9}{40} \cdot {x}^{2} - \left(\frac{27}{2800} \cdot {x}^{4} + \frac{1}{2}\right)\\ \mathbf{else}:\\ \;\;\;\;\frac{x}{x - \tan x} - \sin x \cdot \frac{1}{x - \tan x}\\ \end{array}\]

Reproduce

herbie shell --seed 2020157 
(FPCore (x)
  :name "sintan (problem 3.4.5)"
  :precision binary64
  (/ (- x (sin x)) (- x (tan x))))