# Trigonometric Identities

- There are various
**identities**that can be proven regarding**trigonmetric functions**. In a**right angled triangle**, and since and :

- In a right angled triangle

So: (Hcosθ)^{2}+ (Hsinθ)^{2}= H^{2}

(cosθ)^{2}+ (sinθ)^{2}= 1