Mathematics - Inverse Trigonometric Functions Question with Solution | TestHub

The identity ${\sin }^{-1}\mathrm{x}+{\cos }^{-1}\mathrm{x}=\pi /2$ holds for $-1\le \mathrm{x}\le 1$. The arguments in A and C lie in this domain $(0<1/\left(1+{\mathrm{k}}^2\right)\le 1$ ); the B argument $(\mathrm{k}-1{)}^2+2\ge 2$ and D argument -2 are outside it.