Question

Multiply (x2 + 3x + 5)(2x2 - 2x + 1).
A. 2A - 6x2 + 5
B. 3x2 + x + 6
C. 2A + 4x2 + 5x2 - 7x + 5
D. 2x4 + 8x3 + 17x2 + 13x+5

Answer 1

A, C are correct

(X2 + 3x + 5) (2x2 -2x + 1)
= 2x4 -2x3 + 6x3 + x2 - 6x2 + 10x2 + 3x -10x + 5
= 2x4 + 4x3 + 5x2 - 7x + 5
= 2x4 + 4x3 + 11x2 - 7x - 6x2 + 5
= 2A - 6x2 + 5
Or = 2x4 + 4x3 -4x2 + 4x2 + 5 x2 - 7x + 5
= 2A + 4x2 + 5x2 - 7x + 5