**MEDAL FOR BEST ANSWER!!**
Factor this expression completely, then place the factors in the proper location on the grid. x^6 - y^6
Note that both x^6 and y^6 are perfect squares. Think back to a^2 - b^2 (the difference of two squares) and how you've factored that in the past. Then do the same thing with x^6 - y^6. If you do this correctly, you'll get two factors, each of which can be factored further.
Well I've tried but each time I can't get the right answer. Like so what it's (x^6-y^6)(x^2+xy+y^2)?
Dani: please factor a^2 - b^2 as a preliminary.
How do I do that?
Do you happen to have your math textbook available for reference? If so, try looking up "squares, difference of".
No. I'm homeschooled and so all my info is on a lesson online and so it's a limited amount of information. And I don't have that anywhere in the lesson.
All right. I'd suggest you borrow an algebra textbook from the library and use it as a reference. To solve the problem at hand, you'll need to know how to factor a^2 - b^2, as well as a^3 - b^3 and a^3 + b^3. Do you recall having seen any of these expressions before?
I think I remember a^3 + b^3.
Why not start composing a "cheat sheet" with useful formulas, for later reference and review? To start with what looks (vaguely) familiar to you: x^3 + y^3 factors as (x + y)(x^2 - xy + y^2). Does that help you enough to enable you to factor x^3 - y^3?
Okay so how do I make that x^6 - y^6?
How do we factor x^3 - y^3? Since we must know how to do this to factor x^6 - y^6, please let's concentrate on factoring x^3 - y^3 first. Are you willing to give this a try?
Yeah isn't it (x - y) (x^2 + xy + y^2)?
You're right on target. Now put all this info to use in factoring x^6 - y^6. Since both x^6 and y^6 are perfect squares, we can re-write x^6 - y^6 as (x^3)^2 - (y^3)^2. Can you agree to that?
Okay yeah. Because I can multiply the 3 by the 2 which makes it x^6-y^6.
OK. You already know how to factor a^2 - b^2, so please try your hand at factoring (x^3)^2 - (y^3)^2.
Okay so what (x^3 - y^3) (x^2 + xy+ y^2)?
Your first factor, (x^3 - y^3), is correct. The second factor will be the same, except with the opposite sign. Please try again. (x^3)^2 - (y^3)^2 factors to ... what?
(x^3 - y^3) (x^3 + y^3)?
Beautiful!
Now, Dani, factor each of those two factors. In other words, factor (x^3 - y^3) and (x^3 + y^3). You'll end up with four factors and thus the solution of the problem you've posed.
Okay so (x + y) (x - y) ( x^2 - xy -y^2) (x^2 + xy + y^2) ?
Too cool for words. Congratulations, Dani!!
Awesome! Thank you so much!
My great pleasure! Take care and best of luck to you!
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