SOLUTION: Find all the roots of the equation x^4-4x^3-6x^2+4x+5=0.

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Question 720501: Find all the roots of the equation x^4-4x^3-6x^2+4x+5=0.
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
Find all the roots of the equation x^4-4x^3-6x^2+4x+5=0.
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x = 1 is a root.
Use synthetic division to help find others:
1)....1....-4....-6....4....5
......1....-3....-9...-5..|..0
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Find roots of x^3 - 3x^2 -9x -5
x = -1 is a root.
Use synthetic divisin to help find others:
-1)....1....-3....-9....-5
......1....-4....-5...|..0
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Solve quotient: x^2 -4x-5
(x-5)(x+1) = 0
x = 5 or x = -1
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All The roots: x = 1, -1, -1, 5
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Cheers,
Stan H.
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