SOLUTION: factor the following sums or differences of two cubes b^3-8

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Question 37924: factor the following sums or differences of two cubes
b^3-8
Answer by Earlsdon(6294) About Me  (Show Source):
You can put this solution on YOUR website!
The general form for factoring the difference of two cubes is:
A%5E3-B%5E3+=+%28A-B%29%28A%5E2%2BAB%2BB%5E2%29
In your problem:b%5E3-8 can be written as:%28b%29%5E3-%282%29%5E3 so that A = b and B = 2
b%5E3-8+=+%28b-2%29%28b%5E2%2B2b%2B2%5E2%29 Simplify.
b%5E3-8+=+%28b-2%29%28b%5E2%2B2b%2B4%29