This video lecture from Conic Sections (F.Sc. second year Mathematics) covers: some theorems on circle like the tangent to a circle at any point of the circle is perpendicular to the radial segment at that point and the perpendicular at the outer end of a radial segment is tangent to the circle. 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.