Question

(4x-2) (x2+7x-3)=Ax3+Bx2+Cx+D
Tentukan nilai A+2B-3C+4D

Answer 1

(4x - 2)(x^2 + 7x - 3) = Ax^3 + Bx^2 + Cx + D
4x^3 + 28x^2 - 12x - 2x^2 - 14x + 6 = Ax^3 + Bx^2 + Cx + D
4x^3 + 26x^2 - 26x + 6 = Ax^3 + Bx^2 + Cx + D

A = 4
B = 26
C = -26
D = 6

A + 2B - 3C + 4D
= 4 + 2 × 26 - 3 × (-26) + 4 × 6
= 4 + 52 + 78 + 24
= 158