Polynomial Equation: solve 7x^3+3x^2-29x+11 in real numbers  TOPIC_SOLVED

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Polynomial Equation: solve 7x^3+3x^2-29x+11 in real numbers

Postby balkenator on Mon Jul 06, 2009 2:33 pm

The directions are to "solve the equation in the real number system" and the following polynomial is given:
7x^3+3x^2-29x+11

I need to "find the real solutions" to the equation.
I found that 11/7 is a zero, but after plugging it in, I come up with (7x-11)(x^2+14x-7) First of all, I don't know if that factorization is right, and secondly, I cannot figure out how to factor it further so that I can do another synthetic division. can someone help please? this is a really nasty problem... :confused:
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Postby stapel_eliz on Mon Jul 06, 2009 6:00 pm

Once you have a quadratic factor, why not solve by applying the Quadratic Formula? :wink:
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Re: Polynomial Equation: solve 7x^3+3x^2-29x+11 in real numbers

Postby balkenator on Mon Jul 06, 2009 8:21 pm

I acutally DID try to use the Quadratic formula, but the answer that i got was really wrong- and I know it's because I haven't factored it the right way.... hence, i am back to my original post.
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Re: Polynomial Equation: solve 7x^3+3x^2-29x+11 in real numbers  TOPIC_SOLVED

Postby Martingale on Tue Jul 07, 2009 12:48 am

balkenator wrote:...
7x^3+3x^2-29x+11
... I come up with (7x-11)(x^2+14x-7) ...



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