SOLUTION: Finf the rational roots of (4x to the thrid power -3x-1=0). Explain the process you use and show work

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Question 456035: Finf the rational roots of (4x to the thrid power -3x-1=0). Explain the process you use and show work
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
Find the rational roots of (4x to the third power -3x-1=0).
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4x^3-3x-1 = 0
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The sum of the coefficients is zero so x=1 is a root
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Use synthetic division:
1).....4....0....-3....-1
........4....4.....1...|..0
Quotient: 4x^2+4x+1
Solve 4x^2+4x+1 = 0
Factor:
(2x+1)(2x+1) = 0
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x = -1/2 with multiplicity 2
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Cheers,
Stan H.
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