Question

INCREDIBLY URGENT!!
verify tan(α+β) = [tan(α)+tan(β)] / [1 + tan(α)tan(β)]
- use the angle sum formula for cosine, the angle sum formula for sine, and the identity tan(x) = sin(x)/cos(x) to verify it.

Answer 1

Answer:

When you see a formula like this, try to operate, so you will see some identities sooner or later. In this case, we have a substraction identity:

\frac{cos ( \alpha  -  \beta )}{cos  \alpha cos  \beta }  =  \frac{cos   \alpha cos  \beta + sin \alpha sin  \beta }{cos  \alpha cos  \beta }  = 1 + tan α · tan β

Step-by-step explanation: