# One Two Three Four Five Present!

**Calculus**Level 4

\[ \large \int_{ \frac {\pi}{4} }^{ \frac { \pi }{2} } \frac {\cos 5x + \cos 4x}{1 - 2 \cos 3x} \ dx \]

If the integral above equals to \(\frac1a -\frac1b\), what is the value of \(a+b\)? Give your answer to 3 decimal places.

**Details and Assumptions**

- You may use the approximation \( \sqrt 2 = 1.41421 \)