Two vectors by definition are orthogonal when the angle between them is 90 degrees. It can also be said that they are orthogonal if the scalar product between both vectors is zero. We have then: u = -3i - j v = 2i + 2j u.v = (- 3i - j) (2i + 2j) = - 6-2 u.v = -8 They are not orthogonal vectors. The angle between them is lul = root ((- 3) ^ 2 + (-1) ^ 2) = 3.16227766 lvl = root ((2) ^ 2 + (2) ^ 2) = 2.828427125 The angle between them is: cos (x) = (u.v) / ((lul) * (lvl)) cos (x) = (- 8) / ((3.16227766) * (2.828427125)) cos (x) = - 0.894427191 x = acos (-0.894427191) x = 153.4349488 x = 153.43 Answer: It is not orthogonal Angle between them: x = 153.43
