SOLUTION: the tenth row of Pascal's triangle begins: 1, 10, 45, 120, 210... Use the triangle to answer the following questions a. find the eighth term in the expansion of (x+1)^10 b. fin

Algebra ->  Sequences-and-series -> SOLUTION: the tenth row of Pascal's triangle begins: 1, 10, 45, 120, 210... Use the triangle to answer the following questions a. find the eighth term in the expansion of (x+1)^10 b. fin      Log On


   

Question 81950This question is from textbook
: the tenth row of Pascal's triangle begins: 1, 10, 45, 120, 210... Use the triangle to answer the following questions
a. find the eighth term in the expansion of (x+1)^10
b. find the first four terms in the expansion of (x-y)^11 This question is from textbook

Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
a. find the eighth term in the expansion of (x+1)^10
8th term: 10C3x^3*1^7 = [10*9*8]/[1*2*3*]x^3 = 720/6 x^3 = 120x^3
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b. find the first four terms in the expansion of (x-y)^11
11C11x^11(-y)^0 + 11C10x^10(-y)^1+11C9x^9(-y)^2+11C8x^8(-y)^3
=x^11 - 11x^10y + 55x^9y^2 - 165x^8y^3....
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Cheers,
Stan H.