SOLUTION: Find an nth-degree polynomial function with real coefficients satisfying the given conditions. N=3 -4 and 8+2 are zeros F(2)=240

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Question 1129264: Find an nth-degree polynomial function with real coefficients satisfying the given conditions.
N=3
-4 and 8+2 are zeros
F(2)=240

Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
Find an nth-degree polynomial function with real coefficients satisfying the given conditions.
N=3
-4 and 8+2i are zeros
F(2)=240
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8-2i must also be a zero
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F(x) = a(x+4)(x-8-2i)(x-8+2i)
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F(x) = a(x+4)[(x-8)^2-(2i)^2]
F(x) = a(x+4)[x^2-16x+64+4]
F(x) = a(x+4)[x^2-16x+68]
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Solve for "a" using F(2) = 240
240 = a(2+4)(4-64+68)
240 = a*6*8
a = 240/48
a = 5
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Ans:: F(x) = 5(x+4)(x^2-16x+68)
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Cheers,
Stan H.
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