CAPE Pure Mathematics Unit 2 · May/June 2016 · Paper 1 · Question Q9

\int \frac{1}{x^2 + 4} \, dx =

1. (A)\tan^{-1}\left(\frac{x}{2}\right) + c
2. (B)2\tan^{-1}(2x) + c
3. (C)\tan^{-1}(2x) + c
4. (D)\frac{1}{2}\tan^{-1}\left(\frac{x}{2}\right) + c