The vectors and are perpendicular. Find .

Answer and explanation

Correct answer: B.

  1. Step 1: Perpendicular vectors have dot product 0. Step 2. , so . **Answer: . Why not the others:** The other values come from a wrong sign or from treating the vectors as parallel.

Practise more Algebra, Calculus, Geometry and Probability.

Free questions with an explanation for every one, and full timed NMT National Multi-Subject (Ukraine) mock tests.