Answer:
a = -3/2 = -1.5
Step-by-step explanation:
(1+ax) (2+3x)³
Formula
(a+b)^3=a^3+3a^2b+3ab^2+b^3
(1 + ax) [ 2^3 + 3*2^2*3x + 3*2*(3x)^2 + (3x)^3]
(1 + ax) [ 8 + 12*3x + 6*9x^2 + 27x^3]
8 + 12*3x + 6*9x^2 + 27x^3 + 8ax + 36ax^2 + 54ax^3 + 27ax^4
coefficient of x^2 is zero
54x^2 + 36ax^2
54 + 36a = 0
36a = -54
a = -3/2
