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4 votes
Give an example of an odd polynomial of degree 3, which is zero when x=-3.

User Mwilcox
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2 Answers

3 votes
ok, so if a zero is at r1, then a factor is (x-r1)
since there are no other roots, it must be only taht root
3rd degree so reaise it to the 3rd power

(x-r1)³
and the root is at x=-3
(x-(-3))³
(x+3)³

answer is f(x)=(x+3)³
also could be x³+27 where it factors to one real root and 2 complex roots
User Diego Oriani
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7.8k points
2 votes
ok, so if a zero is at r1, then a factor is (x-r1)
since there are no other roots, it must be only taht root
3rd degree so reaise it to the 3rd power

(x-r1)³
and the root is at x=-3
(x-(-3))³
(x+3)³

answer is f(x)=(x+3)³
also could be x³+27 where it factors to one real root and 2 complex roots
User BrOSs
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7.8k points