10. [-/13 Points] DETAILS LARCALC12 11.3.034.MI.SA. This question has several parts that must be completed sequentially. If you skip a part of the question, part. Tutorial Exercise Find the direction cosines and angles of u and show that cos a + cos2 B + cos2 y = 1. u = -3i + 4j + 6k Step 1 Write the vector u = -3i + 4j + 6k in component form. u = (U1 , U21 U/3) = Submit Skip (you cannot come back)