SOLUTION: what are the last three terms of the expansion (a-b)7

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Question 286880: what are the last three terms of the expansion (a-b)7
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
what are the last three terms of the expansion (a-b)7
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6th term: 7C2(a)^2(-b)^5 = -21a^2b^5
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7th term: 7C1(a)^1(-b)^6 = 7ab^6
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8th term: 7C0(a)^0(-b)^7 = -b^7
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Cheers,
Stan H.