Let f(x)=2cos2x and g(x)=1+sin x. - Solve f(x)=g(x) for -pi

Question

Let f(x)=2cos2x and g(x)=1+sin x. - Solve f(x)=g(x) for -pi <= x 2pi. - Hence solve f(2x)=g(2x) for 0 <= x <= pi.

Accepted Answer

(a) $x=-\frac{\pi}{2},\frac{\pi}{6},\frac{5\pi}{6},\frac{3\pi}{2}$. (b) $x=\frac{\pi}{12},\frac{5\pi}{12},\frac{3\pi}{4}$.

IB Math HL Trigonometry Test 1 2012 P1 Q4