Mathematics - Inverse Trigonometric Functions Question with Solution | TestHub

Let $\theta ={\tan }^{-1}x\in (-\pi /2,\pi /2)$. Then ${\cos }^{-1}(\cos 2\theta )=|2\theta |$, so the expression is 2$\theta +|2\theta |=0$ for x≤0 and 4${\tan }^{-1}x$ for x≥0. The right edge of the constant interval is 0.