SOLUTION: Can someone please explain the process for this problem: (x^3+3)^2-9 This is how i get to my answer: x^6+3x^3+3x^3+9-9 x^6+6x^3 The book states the answer is: x^6+3x^3

Algebra ->  Exponents -> SOLUTION: Can someone please explain the process for this problem: (x^3+3)^2-9 This is how i get to my answer: x^6+3x^3+3x^3+9-9 x^6+6x^3 The book states the answer is: x^6+3x^3       Log On


   



Question 352084: Can someone please explain the process for this problem:
(x^3+3)^2-9
This is how i get to my answer:
x^6+3x^3+3x^3+9-9
x^6+6x^3
The book states the answer is:
x^6+3x^3
I'm not understanding why? Any help would be greatly appreciated.

Answer by mananth(16946) About Me  (Show Source):
You can put this solution on YOUR website!
(x^3+3)^2-9
(x^3+3)^2 - (3)^2
This is similar to a^2-b^2 = (a+b)(a-b)
(x^3+3+3)(x^3+3-3)
(x^3+6)(x^3)
x^6 +6x^3
....
m.ananth@hotmail.ca