Consider the equation \displaystyle \tan^2\theta -\sin^2\theta = \sin^2\theta\tan^2\thetatan ​2
​​ θ−sin
​2
​​ θ=sin
​2
​​ θtan
​2
​​ θ.

a) Which of the basic identities will you use first to simplify the left side?

b) Which is the one step before simplifying to the right side?