SOLUTION: n=4;i and 3i are zeros; f(-1)=40 I can't figure out how to turn it into a polynomial function.

Question 1029046: n=4;i and 3i are zeros; f(-1)=40
I can't figure out how to turn it into a polynomial function.
Answer by stanbon(75887) (Show Source): You can put this solution on YOUR website!
n=4;i and 3i are zeros; f(-1)=40
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Since n is 4, -i and -3i must also be zeros.
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f(x) = a(x-i)(x+i)(x-3i)(x+3i)
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f(x) = a(x^2+2)(x^2+9)
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Since f(-1) = 40, let x = -1 , y = 40; solve for "a"::
a*(1+2)(1+9) = 40
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a = 4/3
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Now you know what f(x) looks like.
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Cheers,
Stan H.
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