# Thread: Trigonometric equation w/ different functions on either side.

1. ## Trigonometric equation w/ different functions on either side.

I could kill my math book for not having a similar example. I honestly don't even remember going over this.

cos x+11=sin 3x-9 ; Find x

I think what's really confusing me is the different functions on either side. The book has examples for quadratics, but nothing similar to this. I tried roundabout logic a few times, but I'm still having trouble with the setup/completion.

I don't neccesarily need the answer, but how to solve.

~Wynne

2. Try isolating one of the functions on one side of the equation, then squaring both sides. You can use the Pythagorean Identity on the isolated function and rearrange to get a quadratic you can solve.