$\int_0^\infty\:\frac{\arctan(ax)\arctan(bx)}{x^2}\:dx$ integralini çözün

Question

$$\large\int_0^\infty\:\frac{\arctan(ax)\arctan(bx)}{x^2}\:dx\:\:\:,\:\:\:a,b\in\mathbb{R}$$

İntegralini çözün.