SOLUTION: what is the third term in the expansion of (2x-3y)^3

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Question 880702: what is the third term in the expansion of (2x-3y)^3
Found 2 solutions by jim_thompson5910, Alan3354:
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
%282x-3y%29%5E3


%282x-3y%29%282x-3y%29%282x-3y%29


%282x-3y%29%284x%5E2-6xy-6xy%2B9y%5E2%29


%282x-3y%29%284x%5E2-12xy%2B9y%5E2%29


2x%284x%5E2-12xy%2B9y%5E2%29-3y%284x%5E2-12xy%2B9y%5E2%29


8x%5E3-24x%5E2y%2B18xy%5E2-12x%5E2y%2B36xy%5E2-27y%5E3


8x%5E3-36x%5E2y%2B54xy%5E2-27y%5E3


So the third term is 54xy%5E2

Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
what is the third term in the expansion of (2x-3y)^3
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%28a-b%29%5E3+=+a%5E3+-+3a%5E2b+%2B+3ab%5E2+-+b%5E3
Sub 2x for a and (-3y) for b