SOLUTION: Find the coefficient of the term a⁶bł in the binomial expansion of the expression (a - 4b)⁹ A.) 5,376 B.) 344,064 C.) -5,376 D.) -344,064

Algebra ->  Finance -> SOLUTION: Find the coefficient of the term a⁶bł in the binomial expansion of the expression (a - 4b)⁹ A.) 5,376 B.) 344,064 C.) -5,376 D.) -344,064      Log On


   

Question 1081386: Find the coefficient of the term a⁶bł in the binomial expansion of the expression (a - 4b)⁹
A.) 5,376
B.) 344,064
C.) -5,376
D.) -344,064
Answer by Boreal(15235) About Me  (Show Source):
You can put this solution on YOUR website!
The leading coefficient will be 9C6=84
The (-4b)^3 will be -64b^3
84*-64=-5376
C
the approach to these is for the k th term, it is first term^k, second term (including the sign)^(n-k), with the leading coefficient's being nCn-k