SOLUTION: what is the eigth term in expansion (x-2)^10

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Question 887255: what is the eigth term in expansion (x-2)^10
Answer by Edwin McCravy(20055) About Me  (Show Source):
You can put this solution on YOUR website!
what is the eigth term in expansion (x-2)^10

The Rth term of %28A%2BB%29%5EN is given by
this expression:

%28matrix%282%2C1%2CN%2CR-1%29%29A%5E%28N-R%2B1%29B%5E%28R-1%29

where %28matrix%282%2C1%2Cp%2Cq%29%29 means the same as C%28p%2Cq%29 or pCq 

In your problem A=x, B=-2, N=10, R=8

So we substitute those and get

 %28matrix%282%2C1%2C10%2C8-1%29%29%28x%29%5E%2810-8%2B1%29%28-2%29%5E%288-1%29

%28matrix%282%2C1%2C10%2C7%29%29%28x%29%5E%283%29%28-2%29%5E%287%29

%28120%29%28x%5E3%29%28-128%29

-15360x%5E3

Edwin