Question

The product of (a + b)(a − b) is a2 − b2.

Sometimes
Always
Never
Please explain so I can understand this a bit more.

Answer 1

well use the FOIL method to see if it's only sometimes or never

Answer 2

what about the a2-b2?

Answer 3

@xspoon do you know how to do the F.O.I.L method of expansion?

Answer 4

Well, when you foil it out then it would be a2 + 2ab - 2ab +b2 and then the middle values would cancel out.

Answer 5

and notice in doing this we never put in stipulations on a,b. We never divided by a or b, so we dont have to worry about them not being 0....ect.

so this must always be true.