v = <x2-x1, y2-y1>
Given a vector with magnitude |v| and direction angle θ, then the components of the vector are given as2. Find the horizontal and vertical components of each vector. Write an equivalent vector in the form "v = a1i + a2i"
Magnitude = 4, Direction angle = 15PI/8
<|v|cos θ, |v|sin θ>