SOLUTION: how do I solve this problem "find the 8th term in the expansion of (2c-3d)^14

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Question 331422: how do I solve this problem
"find the 8th term in the expansion of (2c-3d)^14
Answer by Edwin McCravy(20060) About Me  (Show Source):
You can put this solution on YOUR website!
Find the 8th term in the expansion of (2c-3d)^14 

The kth term in the expansion of %28A%2BB%29%5En is given
by the formula:

%28matrix%282%2C1%2Cn%2Cr-1%29%29%2AA%5E%28n-r%2B1%29%2AB%5E%28r-1%29 or sometimes it's written C%28n%2Cr-1%29%2AA%5E%28n-r%2B1%29%2AB%5E%28r-1%29

In your problem,

A=2c, B=-3d, n=14, r=8

So we substititute:

%28matrix%282%2C1%2C14%2C8-1%29%29%2A%282c%29%5E%2814-8%2B1%29%2A%28-3d%29%5E%288-1%29 or C%2814%2C8-1%29%2A%282c%29%5E%2814-8%2B1%29%2A%28-3d%29%5E%288-1%29

%28matrix%282%2C1%2C14%2C7%29%29%2A%282c%29%5E7%2A%28-3d%29%5E7 or C%2814%2C7%29%2A%282c%29%5E7%2A%28-3d%29%5E7



%283432%29%2A128%2Ac%5E7%2A%28-2187%29d%5E7

-960740352%2Ac%5E7%2Ad%5E7

Edwin