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Math Help - function

  1. #1
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    function

    Given P(x) = x^3 - 3x^2 - 5x
    a.evaluate P9x) for each integer value of x from -3 through 5
    b. Find all zeros of P(x)
    d. Prove that 5 is an upper bound on the zeros of P(x)
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  2. #2
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    Re: function

    a. Do you expect us do this for you?

    b. Part (a) gives you one zero; use polynomial long division to get a quadratic equation, which gives you the other two zeros.

    c. Estimate the value of square roots from (b). E.g., \sqrt{29}<\sqrt{36}=6.
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  3. #3
    MHF Contributor

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    Re: function

    Quote Originally Posted by doctorbleachers View Post
    Given P(x) = x^3 - 3x^2 - 5x
    a.evaluate P9x) for each integer value of x from -3 through 5
    Do you not understand that this is integer arithmetic? Can you not multiply, add, and subtract integers?

    b. Find all zeros of P(x)
    You can factor an "x" out to P(x) easily, leaving a quadratic term. Do you know the quadratic formula?

    d. Prove that 5 is an upper bound on the zeros of P(x)
    You just need an estimate of the square root that shows up in (b).

    (What happened to (c)?)
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