Inscribed polygons and the circle limit

This animated segment demonstrates the 'Method of Exhaustion' (Guo Yuan Shu). It shows how increasing the number of sides $n$ of an inscribed regular polygon causes its perimeter $P_n$ to converge to the circle's circumference. The video lists calculations for $n=4, 8, 16, 32, 64$ and concludes with the formal epsilon-N definition of a sequence limit.

Before you watch

• Trigonometric functions (Sine rule/Angle bisection)
• Properties of real numbers and inequalities