SOLUTION: Please help me solve this problem: Find the eight term in the expansion of (a + b)10 thank you!

Algebra ->  Sequences-and-series -> SOLUTION: Please help me solve this problem: Find the eight term in the expansion of (a + b)10 thank you!      Log On


   

Question 632016: Please help me solve this problem:
Find the eight term in the expansion of (a + b)10
thank you!
Answer by nerdybill(7384) About Me  (Show Source):
You can put this solution on YOUR website!
(a + b)^10
eighth term:
10C7 a^(10-7)b^7
10C7 a^3b^7
10!/7!(10-7)! a^3b^7
(8*9*10)/3! a^3b^7
(8*9*10)/(3*2*1) a^3b^7
(8*9*10)/(1*2*3) a^3b^7
(4*9*10)/(1*3) a^3b^7
(4*3*10) a^3b^7
120a^3b^7