SOLUTION: How do I find the rational zeros of this equation? {{{3x^3+8x^2-3x-8}}}

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Question 140516: How do I find the rational zeros of this equation? 3x%5E3%2B8x%5E2-3x-8
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
How do I find the rational zeros of this equation? 3x%5E3%2B8x%5E2-3x-8
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Since the coefficients add up to zero, x=1 is a root of the statement:
Use synthetic division to find the quotient.
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1)....3....8....-3....-8
.......3....11....8..|..0
Quotient: x^2 + 11x + 8
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Use the quadratic formula to find the remaining zeroes:
x = [-11 +- sqrt(121 -4*1*8)]/2
x = [-11 +- sqrt(89)]/2
x = [-11+sqrt(89)]/2 or x = [-11-sqrt(89)]/2
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Cheers,
Stan H.