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Math Help - Rational Zeros of a function

  1. #1
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    Rational Zeros of a function

    Find all rational zeros of the function:

    f(x)=25x^4+25x^3-154x^2-4x+24


    ok i found the two zeros 2 and -3, now i dont know how to factor it please help i dont understand how to get the answear

    (x-2)(x+3) (.....
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  2. #2
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    Re: Rational Zeros of a function

    Multiply the two that you found to get x^2+x-6 and then divide by that.

    I can't teach you polynomial division on here but you could choose a video from here..

    polynomial division - YouTube.
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  3. #3
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    Re: Rational Zeros of a function

    hey yep i did long division and got -8x as a remainder, how do i procede??
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  4. #4
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    Re: Rational Zeros of a function

    Did you watch one of the videos?
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  5. #5
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    Re: Rational Zeros of a function

    Top line 25x^2-4 how do i prosede??
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  6. #6
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    Re: Rational Zeros of a function

    Yes that's correct. Now factorise 25x^2-4. It's a difference of two squares.

    You could also look at this page

    (25x^4+25x^3-154x^2-4x+24)/(x^2+x-6) - Wolfram|Alpha
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  7. #7
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    Re: Rational Zeros of a function

    i dont really get the website. Now you get (5x-2)(5x+2) what i do next??
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  8. #8
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    Re: Rational Zeros of a function

    So now you have (x-2)(x+3)(5x-2)(5x+2)=0.

    The product will be zero whenever one of the factors is zero.
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  9. #9
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    Re: Rational Zeros of a function

    You now have (x-2)(x+3)(5x-2)(5x+2)=0 So x=2 or -3 or 2/5 or -2/5
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  10. #10
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    Re: Rational Zeros of a function

    does this question have anything to do with imagenery numbers
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