Question

Which expression represents the product or x3+2x-1 and x4 - x3+3?

Answer 1

4th option

Explanation:

(x³ + 2x - 1)(
`x^(4)` - x³ + 3)

Each term in the second factor is multiplied by each term in the first factor, that is

x³(
`x^(4)` - x³ + 3) + 2x(
`x^(4)` - x³ + 3) - 1 (
`x^(4)` - x³ + 3) ← distribute parenthesis

=
`x^(7)` -
`x^(6)` + 3x³ + 2
`x^(5)` - 2
`x^(4)` + 6x -
`x^(4)` + x³ - 3 ← collect like terms

=
`x^(7)` -
`x^(6)` + 2
`x^(5)` - 3
`x^(4)` + 4x³ + 6x - 3