SOLUTION: Could you please help me factor this problem completely? 3b^3-81d^3 Thank you!!

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Question 204279: Could you please help me factor this problem completely?
3b^3-81d^3
Thank you!!
Answer by Earlsdon(6294) About Me  (Show Source):
You can put this solution on YOUR website!
Factor completely:
3b%5E3-81d%5E3 First, factor out a 3.
3%28b%5E3-27d%5E3%29 Now do you see that the parentheses contain the difference of two cubes?
The difference of two cubes can be factored thus:
A%5E3-B%5E3+=+%28A-B%29%28A%5E2%2BAB%2BB%5E2%29 Applying this to the group in the parentheses, we get:
highlight%283%28b-3d%29%28b%5E2%2B3bd%2B9d%5E2%29%29