SOLUTION: 27a^3 - 343b^3

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Question 181812: 27a^3 - 343b^3
Answer by Mathtut(3670) About Me  (Show Source):
You can put this solution on YOUR website!
lets rewrite this
:
%283a%29%5E3-%287b%29%5E3now we see this is the difference of cubes
:
of the form a%5E3-b%5E3in our case a is 3a and b is 7b
:
highlight%28%283a-7b%29%289a%5E2%2B21ab%2B49b%5E2%29%29 just plugging in to the difference of cubes formula