SOLUTION: Please help w/ the following: Multiply: [{x+2}^3] Thank you.

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Question 55452: Please help w/ the following:
Multiply:
[{x+2}^3]
Thank you.
Found 2 solutions by tutorcecilia, funmath:
Answer by tutorcecilia(2152) About Me  (Show Source):
You can put this solution on YOUR website!
[{x+2}^3]
(x+2)(x+2)(x+2)[Expand]
(x^2+4x+4)(x+2)[FOIL]
(x^3+4x^2+4x+2x^2+8x+8)[Multiply by (x+2)
x^3+6x^2+12x+8 [Combine like-terms]

Answer by funmath(2933) About Me  (Show Source):
You can put this solution on YOUR website!
Multiply:
[{x+2}^3]
%28x%2B2%29%5E3
%28x%2B2%29%28x%2B2%29%28x%2B2%29 Multiply the first two first:
%28x%28x%29%2Bx%282%29%2B2%28x%29%2B2%282%29%29%28x%2B2%29
%28x%5E2%2B2x%2B2x%2B4%29%28x%2B2%29 Combine like terms:
%28x%5E2%2B4x%2B4%29%28x%2B2%29 Distribute all the terms in the first parenthesis through all the terms in the second parenthesis:
x%5E2%28x%29%2Bx%5E2%282%29%2B4x%28x%29%2B4x%282%29%2B4%28x%29%2B4%282%29
x%5E3%2B2x%5E2%2B4x%5E2%2B8x%2B4x%2B8 Combine like terms:
highlight%28x%5E3%2B6x%5E2%2B12x%2B8%29
:
Another way to do it is by the formula, the advantage is that it's shorter. The disadvantage is, having to memorize yet another formula:
highlight%28%28a%2Bb%29%5E3=a%5E3%2B3a%5E2b%2B3ab%5E2%2Bb%5E3%29
a=x and b=2
%28a%2Bb%29%5E3=%28x%29%5E3%2B3%28x%29%5E2%282%29%2B3%28x%29%282%29%5E2%2B%282%29%5E3
=x%5E3%2B6x%5E2%2B12x%2B8
Happy Calculating!!!