Question

Find the exact solutions. Half or double angle identity?

Answer 1

\[3+ \cos(2x) = 2\sin(x) for 0 \le x \le 2\pi\]

Answer 2

Change cos2x to 1-2sin^2x
Then move everything to one side and you will find you have a quadratic

Answer 3

I did that and found that I could not factor: \[2(\sin ^{2}(x)\sin(x)-2)\] Am I being dumb and missing something here?

Answer 4

Is there a minus sign in the middle there?

Answer 5

The sines shouldnt be multiplied together, the equation should form a quadratic

Answer 6

Sorry, \[-2(\sin ^{2}(x) + \sin(x) -2)\]