# Trigonometry - Proving Identities

## (based on the Double Angle formulae)

You will be expected to be able to prove a trig. identity such as the examples below. In the videos I show you how to set out an identity and what to look for.

This is a tricky topic and one that I find students give in too quickly. Learn your formulae and have patience.

### Double Angle Formulae

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### Worked Solution to (1)

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