(x +1 )(2x - 2)(3x + 3) = ax3+bx2+cx+dax3+bx2+cx+d What are the values of a, b, c and d?
Options:
(A) 2
(B) 7
(C) 6
(D) 1
(E) 9 Stream of consciousness:
(x + 1)(2x - 2)(3x + 3) = ax3+bx2+cx+dax3+bx2+cx+d
6(x + 1)(x - 1)(x + 1) = ax3+bx2+cx+dax3+bx2+cx+d
6(x2x2 - 1)(x + 1) = ax3+bx2+cx+dax3+bx2+cx+d
6(x3+x2x1)6(x3+x2x1) = ax3+bx2+cx+dax3+bx2+cx+d
6x3+6x26x66x3+6x26x6 = ax3+bx2+cx+dax3+bx2+cx+d
Equating the coefficients of like learns on both the sides, a = 6, b = 6, c = -6 and d = -6.
Thus, the answer is (C).