Question

(3a+2b)(3a-2b)(9a^2+4b^2) ?

Answer 1

Do you want it simplified or expanded?

Answer 2

Note that (a+b)(a-b)=a^2 - b^2. Use this fact to multiply the first two factors together.

Answer 3

Simplified @larryboxaplenty thanks @mathmale

Answer 4

I meant to ask if you need it in expanded form or root form

Answer 5

E.g. like 3x^2+2x+1 or (x+1)(x-1)(x+10)(x-4)

Answer 6

First one @larryboxaplenty

Answer 7

first do a (3a-2b)(9a^2+4b^2)

Answer 8

It's easier to do 1-term * 2 term first than 2 term * 2 term

Answer 9

Ok thanks! @larryboxaplenty

Answer 10

Alternative approach:

(3a+2b)(3a-2b)(9a^2+4b^2) =
(9a^2 - 4b^2)*(9a^2 + 4b^2) =
81a^4 - 16b^2.

That's it.

Answer 11

Thanks! So easy to understand your explanation :) @mathmale