Question

Prove that:
.
tanα+tanβ/tanα-tanβ = sin(α+β)/sin(α-β)

Answer 1

I choose Right Hand Side

Answer 2

\[\frac{ \sin \alpha \cos \beta + \cos \alpha \sin \beta }{ \sin \alpha \cos \beta-\cos \alpha sin \beta}\]

Answer 3

Prove using RHS? and you get what's in the third post?

Answer 4

its the identity

Answer 5

OK, look at the LHS. There are tangents all over the place, so because tanx=sinx/cosx, it seems a good idea to divide both numerator and denominator by sinαcosβ.

Answer 6

TYPO: I meant divide by cosαcosβ!