Have you used this and got the answer? Just saying this because I tried doing tan^2(x) = .... (expanding the tan(x-a)tan(x-b)) and then subbing this tan squared value into tan2x = 2tanx / 1-tan^2(x) . It ends up like a mess up of terms of tanx, tana, tanb which seems unsolvable and it doesnt...
really need help with this, its so hard, if someone can show full steps that'd be a LIFESAVER
I've tried a bunch of things, full method would be awesome
given (tanx)^2=tan(x-a)tan(x-b), show that tan2x=(2sinaxsinb)/(sin(a+b))