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Math Help - Factoring polynomials

  1. #1
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    Factoring polynomials

    Hello, I need help factoring the following: 2x^3 - 5x - 3

    I've gotten as far as using the payback method to get: x^3 - 5x - 6 but I can't seem to go beyond that.

    Help is appreciated, thanks!
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  2. #2
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    Try doing synthetic division. So we have the polynomial 2x^{3}-5x-3=0 Lets try some easy numbers, like -1, 0, 1 to see if they satisfy the polynomial. By plugging in these numbers we can see that -1 is a factor meaning that (x+1) satisfies the polynomial. Now we can do synthetic division: (Make sure to put a 0 for all variables that are missing)

    -1| 2 0 -5 -3
    0 -2 2 3
    2 -2 -3 0

    So now we can see that (x+1)(2x^{2}-2x-3) are factors. Simply do the quadratic equation from here. (Sorry if some of the steps were unclear, I am not that great at explaining)
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  3. #3
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    Quote Originally Posted by vperera View Post
    Hello, I need help factoring the following: 2x^3 - 5x - 3

    I've gotten as far as using the payback method to get: x^3 - 5x - 6 but I can't seem to go beyond that.

    Help is appreciated, thanks!
    Please don't double post. See rule #1 here.

    -Dan
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