Sum and Difference of Two Angles

Go to the derivation of sum and difference of two angles if you want information on where these formulas came from.

1. sin(α+β)=sinαcosβ+cosαsinβ
2. sin(αβ)=sinαcosβcosαsinβ
3. cos(α+β)=cosαcosβsinαsinβ
4. cos(αβ)=cosαcosβ+sinαsinβ
5. tan(α+β)=tanα+tanβ1tanαtanβ
6. tan(αβ)=tanαtanβ1+tanαtanβ