Need help factoring complex algebra?

Question

please help me on these problems, I'm so confused.

factor as indicated:

1.) 1-sin^2 x= ( ) ( )

2.) x^4-7x^2+12= ( )( )( )

3.) e^2x + 2 + e ^ -2x = ( )^2

Answer 1

1.) 1-sin^2 x= (1+ sinx) (1--sinx)

2.) x^4-7x^2+12= (x^2--3)(x^2--4))

3.) e^2x + 2 + e ^ -2x = (e^x + e^-x)^2