Which expression represents the product or x3+2x-1 and x4 - x3+3?
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Answer:
4th option
Step-by-step explanation:
(x³ + 2x - 1)([tex]x^{4}[/tex] - x³ + 3)
Each term in the second factor is multiplied by each term in the first factor, that is
x³([tex]x^{4}[/tex] - x³ + 3) + 2x([tex]x^{4}[/tex] - x³ + 3) - 1 ([tex]x^{4}[/tex] - x³ + 3) ← distribute parenthesis
= [tex]x^{7}[/tex] - [tex]x^{6}[/tex] + 3x³ + 2[tex]x^{5}[/tex] - 2[tex]x^{4}[/tex] + 6x - [tex]x^{4}[/tex] + x³ - 3 ← collect like terms
= [tex]x^{7}[/tex] - [tex]x^{6}[/tex] + 2[tex]x^{5}[/tex] - 3[tex]x^{4}[/tex] + 4x³ + 6x - 3