SOLUTION: Factor the polynominal completely. 27a^3-8b^3

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Question 26619: Factor the polynominal completely.
27a^3-8b^3

Answer by Earlsdon(6294) About Me  (Show Source):
You can put this solution on YOUR website!
You should be able to recognise this expression as the difference of two cubes, for which the factored form is:
A%5E3+-+B%5E3+=+%28A+-+B%29%28A%5E2+%2B+AB+%2B+B%5E2%29 Applying this to your problem:
27a%5E3-8b%5E3+=+%283a%29%5E3-%282b%29%5E3 and...
%283a%29%5E3-%282b%29%5E3+=+%283a-2b%29%289a%5E2%2B6ab%2B4b%5E2%29 You could go a little farther on the second factor:
%283a-2b%29%289a%5E2%2B2%282b%5E2%2B3ab%29%29