Pythagoras' Theorem and pizzas? The theorem is meticulously described here with an animation and extension material that brings the concept to real life (yes, using pizzas!). Among various other sections covered are sine, cosine, tangent and measurements in radians.
Trig ratios in a right-angled triangle
Knowledge of the trigonometric ratios of sine, cosine and tangent is vital in very many fields of engineering, science and maths. This unit introduces them and provides examples of how they can be used to solve problems. Video tutorial 35 mins.