8. [-/6 Points] DETAILS LARCALCET7 11.3.031. MY NOTES ASK YOUR TEACHER Find the direction cosines and angles of u and show that cos2 a + cos B + cos2 y = 1. (Round your answers for the angles to four decimal places. ) u = i + 8j + 4k COS a = = rad cos f = B ~ rad COs y rad\f2. [I3 Points] DETAILS LARCALCET7 11.2.051. MY NOTES ASK YOUR TEACHER Find the component form and magnitude of the vector v with the given initial and terminal points. Then nd a unit vector in the direction of v. Initial point: (4, 6, 0) Terminal point: (4, 1, 8)