Find the angle between the two vectors: u = cos 5π/6 i + sin 5π/6 j and v=cos π/4 i + sin π/4 j

Answer 1

The angle for the direction of vector, v, is θ = tan^-1(v_y/v_x) with the correction of +/- π for v_x < 0. In this case, you are given vy as vsin(θ) and vx as vcos(θ), so you can just read off the angle.

The first vector has angle 5π/6 and the second has angle π/4. The angle between them should be clear.

Take care.