5.05 1. find all solutions to the equation in the interval [0, 2π). cos 2x - cos x = 0 a) 0, two pi divided by three. , four pi divided by three. b) pi divided by six , five pi divided by six , three pi divided by two. c) 0, pi divided by two. , seven pi divided by six. , eleven pi divided by six d) no solution 2. rewrite with only sin x and cos x. sin 3x a) 2 sin x cos2x + cos x b) 2 sin x cos2x + sin3x c) sin x cos2x - sin3x + cos3x d) 2 cos2x sin x + sin x - 2 sin3x 3. find the exact value by using a half-angle identity. cosine of five pi divided by twelve. with answer only if you are sure. you