Question

Factor the following polynomial completely.

-x2y2 + x4 + 4y2 - 4x2

( x + 2)( x + 2)( x + y)( x - y)
( x - 2)( x - 2)( x + y)( x - y)
( x + 2)( x - 2)( x + y)( x - y)

Answer 1

I'm just going to re-arrange the terms for you

\( x^4 - 4x^2 - x^2y^2 + 4y^2 \)

we need to factor by grouping

so that means factoring half and half separately first

so can you factor
\( x^4 - 4x^2\)

and

\( - x^2y^2 + 4y^2\)