3.76   ODE No. 76

$$\boxed{{\displaystyle \frac{\mathrm{d}}{\mathrm{d}x}y\left(x\right)-a\cos \left(y\left(x\right)\right)+b=0}}$$

1. Problem in Latex
2. Mathematica input
3. Maple input

Mathematica: cpu = 0.140018 (sec), leaf count = 116 $$\left\{\{y(x)\to 2{\tan }^{-1}(\frac{a\tanh \left(\frac{1}{2}(x\sqrt{(a-b)(a+b)}-c_1\sqrt{(a-b)(a+b)})\right)}{\sqrt{(a-b)(a+b)}}-\frac{b\tanh \left(\frac{1}{2}(x\sqrt{(a-b)(a+b)}-c_1\sqrt{(a-b)(a+b)})\right)}{\sqrt{(a-b)(a+b)}})\}\right\}$$

Maple: cpu = 0.031 (sec), leaf count = 54 $$\{y\left(x\right)=2\arctan \left(\frac{\tanh (1/2\mathit{\_}\mathit{C}\mathit{1}\sqrt{a^2-b^2}+1/2x\sqrt{a^2-b^2})\sqrt{a^2-b^2}}{a+b}\right)\}$$