Prove the following trig identity
In comments to make it clearer

Question

Prove the following trig identity
In comments to make it clearer

anonymous · Answer

$$\frac{ \sin 3x+\sin x }{ \sin 3x-\sin x }=\frac{ 2 }{ 1-\tan ^{2}x }$$

anonymous · Answer

@jhonyy9 can you help me with this one too?

jhonyy9 · Answer

so depend from what part you wan to go on what part ?

jhonyy9 · Answer

sin3x=sin(2x+x) = ?

jhonyy9 · Answer

can you calculi it using formula sin(a+b) = ?

anonymous · Answer

Yeah I tried that but it became hideously complicated, so I stopped with that
Is there a more efficient way that you know of?

fifciol · Answer

I think there is no simpler way, I did it by first apllying sin(a+b) formula, then reducing terms to sines, and at the end dividing by cos^2x to get the right hand side. If you want calculations, just let me know :)

jdoe0001 · Answer

yeap.... I checked the RHS, no dice, it's about just as lengthy

anonymous · Answer

Alright thanks @Fifciol

anonymous · Answer

And yeah @jdoe0001 working the RHS would have too many different processes to unsimplify it and get the answer you need

anonymous · Answer

Hey @fifciol I'm stuck at -4sin^2x+4/-4sin^2+3
can you help?