Question

Simplify cos^2x-4/cosx+2?

Answer 1

If you mean `(cos^2x-4)/(cosx+2)` the answer is `cosx-2`

Explanation:

(a+b)(a-b)=`a^2-b^2` when multiplied out.

So `(a^2-b^2)/(a+b)=((a+b)(a-b))/(a+b)`
Cancel to get `(a-b)`
Hence the answer