What's the 3rd term of the binomial expansion for (3x + 2y)^3?

Question

A: 18xy^2

B: 15xy^2

C: 54(x^2)y

D: 36xy^2

E: 6xy^2

Answer 1

(a+b)³ = a³+3a²b+3ab²+b³

 

the 3rd term is 3ab²

a=3x, b=2y

 

3(3x)(2y)²

= 9x(4y²)

= 36xy²