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Math Help - Limits!!

  1. #1
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    Limits!!

    Find: lim x^3 -4x /x - 2
    x->2

    head Ache much much! l0l
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  2. #2
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    e^(i*pi)'s Avatar
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    Have you studied L'hopital's Rule?

    Question rewritten in latex: \displaystyle \lim_{x \to 2} \dfrac{x^3-4x}{x-2}
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  3. #3
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    Quote Originally Posted by renii View Post
    Find: lim x^3 -4x /x - 2
    x->2

    head Ache much much! l0l
    If you haven't done L'Hopital then

    \displaystyle \lim_{x \to 2} \dfrac{x^3-4x}{x-2}

    Notice that the numerator factors to be \displaystyle x(x^2 - 4) = x(x + 2)(x - 2)

    -Dan
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  4. #4
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    thx uu Dan!! nyce
    iGot dha answer that is in the book in the answers section when i did it your way..thx uu agen for uu kind cooperation tonight...it is grealty appreaciated
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  5. #5
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    Important thing to know: when you are taking a limit of a rational function (one polynomial over another) the only time there is any difficulty is when both numerator and denominator are equal to 0. And, if x= a makes a polynomial 0, then x- a must be a factor!
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