In a two-dimensional motion of a particle, the particle moves from point A, with position vector r→1, to point B, with position vector r→2. If the magnitudes of these vectors are, respectively, r1 = 3 and r2 = 4 and the angles they make with the x - axis are find the θ1=75∘ and θ2=15∘, respectively, then of the displacement vector.