SOLUTION: Please help me find the first three terms in this expansion: (x+3y)^20

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Question 326189: Please help me find the first three terms in this expansion:
(x+3y)^20
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
find the first three terms in this expansion:
(x+3y)^20 = x^20 + 20C19*x^19(3y) + 20C18*x^18(3y)^2 +....
= x^20 + 20*3 x^19y + 180*9 x^18y^2.....
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= x^20 + 60x^19h + 1620x^18y^2....
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Cheers,
Stan H.
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