Question

coefficient of the second term in the expansion of the binomial (4x+3y)^3

Answer 1

(16x^2 + 24xy + 9y^2)( 4x + 3y )
=64x^3 + 48x^2y + 96x^2y + 72xy^2 + 36 xy^2 + 27y^3
=64x^3 + 144x^2y + 108xy^2 + 27y^3
If the second term is x^2y, then the answer is 144. :)

Answer 2

i use the formula

(r + 1)th term of (x + a)^n = nCr x^(n-r) a^r

where nCr =number of combinations r in n

Answer 3

= 3C1 (4x^)2* 3y
= 3*16 x^2* 3y
= 144 x^2 y