Question

what is the coefficient of x2 in the expansion of (x + 2)3?

Answer 1

Given, Coefficient of x^2 in (x+2)^3.

W.K.T Binomial expansion of (x+a)^3 is x^3+3C1 *x^2a+3C2xa^2+3C3a^3.

So, coefficient of x^2 in (x+2)^3 is

3C1 * 2

3 * 2 = 6.

Hope this helps!

Answer 2

The coefficient of #x^2# in the expansion of #(x+2)^3# is #6#

Explanation:

Binomial expansion of #(x+a)^3# is

#x^3+^3C_1x^2a+^3C_2xa^2+^3C_3a^3#

Hence coefficient of #x^2# in #(x+2)^3# is

#color(white)+^3C_1xx2#

= #3xx2=6#