1.Find the position vector (i.e. the direction vector) from the point P(4,7,8)to the pointQ(1,1,?3)

2.

(1 point) 2 1 Let c = -2 (a) Compute | | | = (b) Find the unit vector u in the direction of I. 1 =(1 point) Let u and v be orthogonal vectors in R" , prove that | |u - ]|2 = |/u|12 + 11012. Proof: Since u and v are orthogonal then from which it follows that, v 112112 + 1101 12 A. (u - V) . (u - V) B. u . D =0 c. |lu - all . |lu + all D. (U1, U2, (3) . (V1, U2, V3) = 0 E. |1412 + 1171//41 -1811/411 +11-81/2 F. (u . u + v . v) - 2(u . v) Q. E. D.(1 point) Determine whether each pair of vectors are parallel , orthogonal , or neither [Note: Only 2 attempts are given on this problem.] 20 (a) a = 4 and b 20 -5 32 Answer. 20 (b) a = 4 and b = 20 -5 -25 Answer. 20 (C) a = and b 20 -5 -25 Answer:(1 point) Find the angle o in radians between the vectors -3 1 -4 -5 -5 2 0 = Note: Round to at least four decimal places.\f(1 point) 3 -3 Let a = 2 and b : 1 5 (a) Compute the following dot product. a . b = (b) Is the angle between the vectors acute , obtuse or right? (c) Compute the following lengths. llall = 1b/I =