Hello, I am new here but I’m not big on many words so I’m just going to go right to the reason i am here.

I am having a small trigonometry problem.

I have this equation

sin(2x)=0.7cos(2x)

and I am supposed to solve this where x is equal to or between 0 and 2pi

What I have tried is:

0.75*2*cos(x)^2-2sin(x)cos(x)=0

2(0.75cos(x)-sin(x))=0

Now, I see that I have done something wrong because when i tried inputting this into my calculator using the wonderful "Solve" function I get answers nothing like the answers listen in the back of the book. And second, I cannot see any way to get any more than two solutions from this. (Not like the four solutions I am supposed to get)

Now, I am having similar problems with all the other similar problems, so I am missing something important in general here. Anyone