This video lecture from Vectors (F.Sc.second year Mathematics) covers: Question 3-4 of exercise 7.3. In these questions we find a constant when we are given with two perpendicular vectors. We also find a constant when we are given with three vertices of a right triangle. Find more e-learning material and educational video lectures in Urdu at maktab.pk. These videos are free to use for promotional and commercial purpose by keeping the credits to Maktab.