Question

How do you perform multiplication and use the fundamental identities to simplify `(2cscx+2)(2cscx-2)`?

Answer 1

see below

Explanation:

`(2 csc x+2) (2csc x-2)=4csc^2x-4cscx+4cscx-4`

`=4csc^2x-cancel (4cscx)+cancel (4cscx)-4`

`=4csc^2 x-4`

`=4(csc^2x-1)`--> Use the identity `1+cot^2x=csc^2x`

`=4cot^2x`