Question

Multiply these polynomials.

(5x2 + 2x)(3x2 - 7x + 4)

A. 15x4 - 29x3 + 20x2 + 8x
B. 15x4 - 35x3 + 6x2 + 8x
C. 15x4 - 29x3 + 6x2 + 8x
D. 15x4 - 35x3 + 20x2 + 8x

Answer 1

When we multiply the polynomials we will get:
(5x^2+2x)(3x^2-7x+4)
=5x^2(3x^2-7x+4)+2x(3x^2-7x+4)
=15x^4-35x^3+20x^2+6x^3-14x^2+8x
=15x^4+(6x^3-35x^3)+(20x^2-14x^2)+8x
=15x^4-29x^3+6x^2+8x
The correct answer is C