9. The position vectors of point P and Q are given by r1 = 2i + 3j - k, r2 = 4i - 3j + 3k. Determine PQ in terms of rectangular unit vector i, j, and k and find its magnitude.
9. The position vectors of point P and Q are given by r1 = 2i + 3j - k, r2 = 4i - 3j + 3k. Determine PQ in terms of rectangular unit vector i, j, and k and find its magnitude.