Solve cos(x)=sin(2x)−cos(3x)\cos(x) = \sin(2x) - \cos(3x)cos(x)=sin(2x)−cos(3x) for x∈[0,π]x \in [0, \pi]x∈[0,π].
π/6,π/2,5π/6\pi/6, \pi/2, 5\pi/6π/6,π/2,5π/6
π/4,3π/4\pi/4, 3\pi/4π/4,3π/4
π/3,2π/3\pi/3, 2\pi/3π/3,2π/3
0,π/2,π0, \pi/2, \pi0,π/2,π