(a) Express 3cosx + 2sinx in the form Rcos(x – α), where R and α are constants with R 1 0 and

0° < α < 90°. [3]

(b) Find all values of x between 0° and 360° satisfying

3cosx + 2sinx = 1. [3]

For (a), I have $\displaystyle \sqrt{13}\ cos\ (x - 33.7)$

and in (b), I got up to saying $\displaystyle cos\ (x - 33.7) = \frac{1}{\sqrt1{3}}$, but I have no idea what is done after this to get the values of x.

How is this done? Thanks if you're able to help me (Nod)