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January 6th, 2014, 10:47 AM   #1
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factor

Hello, can someone show me steps to factor:

2x^3 -9x^2 -11x +30

Thank you.
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January 6th, 2014, 11:32 AM   #2
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Math Focus: Calculus/ODEs
Re: factor

Can you use the rational roots theorem to find a rational root, and then use division to obtain a linear and quadratic factor?
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January 6th, 2014, 01:06 PM   #3
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Re: factor

yes.

wish there was an easier way
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January 6th, 2014, 03:09 PM   #4
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Re: factor

Quote:
Originally Posted by Kinroh
yes.

wish there was an easier way
Well, you could write:

2x^3 -9x^2 -11x +30 = 2x^3 -10x^2 + x^2 - 5x -6x +30 = 2x^2(x - 5) + x(x - 5) - 6(x - 5) = (x - 5)(2x^2 + x - 6) = (x - 5)(2x - 3)(x + 2)
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