Question

Multiply and simplify
I've read the book a million times and still feel confused as to how to do everything
a^3+a^2b+a+b/9a^3+9a * 16a^2/8a^2-8b^2

Answer 1

a^3+a^2b+a+b = (a+b)(a^2+1)
9a^3+9a = 9a(a^2+1)
So, the first factor is (a+b)/9a

8a^2-8b^2 = 8(a-b)(a+b)

Now multiply and you have

(a+b)(16a^2)
----------------------
(9a)(8)(a+b)(a-b)

= 2a / 9(a-b)