SOLUTION: 8x^3-64

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Question 186253: 8x^3-64
Answer by nerdybill(7384) About Me  (Show Source):
You can put this solution on YOUR website!
we can rewrite:
8x^3-64
.
as:
(2x)^3-(4)^3
.
Now, it is a "difference of cubes" -- a "special factor"
a^3 – b^3 = (a – b)(a^2 + ab + b^2)
.
(2x)^3-(4)^3
= (2x – 4)((2x)^2 + (2x)(4) + 4^2)
= (2x – 4)(4x^2 + 8x + 16)
= 2(x – 2)4(x^2 + 2x + 4)
= 8(x – 2)(x^2 + 2x + 4)