What is the coefficient of the third term in the binomial expansion of (a + b)6?
1
15
20
90

For the binomial expansion use following formula:

When n=6, then

The third term in this expansion is the coefficient of the third term is 15.

correct choice is B

10a^3+277a^2-132a-792

step-by-step explanation:

(2a+11)(5a-12)(foil)

=10a^2-24a+55a-132 =10a^2+31a-132

(10a^2+31a-132)(a+6)

=10a^3+60a^2+31a^2+186a^2-132a-792 =10a^3+277a^2-132a-792

i hope this is what you are looking for : )