Question

(x^{4}) (3x^{3}-2) (4x^{2}+5x)

Answer 1

The expression becomes 12x^7+6x^6-10x^5.

Answer 2

let's show your

x^4(3x^3-2)(4x^2+5x)

(x^4(3x^3-2))(4x^2+5x)

(x^4(3x^3-2))(4x^2)+(x^4(3x^3-2))(5x)

12x^9+15X^8-8x^6-10x^5

the answer was 12x^9+15^8-8x^6-10x^5

hope that helps you