IGCSE Introduction to Calculus animated powerpoint. The gradient ratio as rise-over-run and the limit for a tangent to a curve as the 鈥榙erivative鈥�. Examples of the limit/derivative for straight line, a parabola and a cubic. The use of the derivative to find 鈥榯urning points鈥�, and the distinction between a local maximum and a local minimum. 15 slides.