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If -3+i is a root of the polynomial function f(x), which of the following must be a root of f(x)?

a. -3-i
b. -3i
c. 3-i
d. 3i

User Mornaner
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2 Answers

5 votes
When dealing with imaginary numbers as roots of a polynomial, you will see that they always occur in conjugates. So the other root that goes with this one is -3 - i. This will always be the case.
User Chasbeen
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4 votes
use the conjugate of the 1st solution to find the second. which is -3 - i. or a
User Xesina
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