Hello!

Firstly, thank you for looking at my question! I am new here and although I seem to be able to pick up mathematical concepts rather well, this one problem is absolutely impossible for me to figure out. I know the answer - I just don't know how to get there! I created an image of my problem so its easier to see what I am talking about. Here is the equation:

Essentially, what I am able to get is this:

(sin^2 x)/(cos^2 x) = tan^2 x

-(tan x)/ -(cot x) = 1

tan^2 x - 1 does not equal tan^2 x

Any help would be super greatly appreciated, thank you very much!

-Joshua