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Question 249669: If the equation x^4+ax^2+bx+c=0 has roots 1,2,3 Find C
Answer by stanbon(75887)   (Show Source):
You can put this solution on YOUR website! If the equation x^4+ax^2+bx+c=0 has roots 1,2,3 Find C
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If x = 1: 1+a + b + c = 0
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If x = 2: 16 +4a + 2b + c = 0
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If x = 3: 81 + 9a + 3b + c = 0
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Rearrange and solve for a,b,c
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a + b + c = 0
4a + 2b + c = -16
9a + 3b + c = -81
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I used a matrix method to get:
a = -(49/2)
b = 115/2
c = -33
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Cheers,
Stan H.
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