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Math Help - tangent slope of f

  1. #1
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    tangent slope of f

    what is the tangent slope of the f(x)= \frac{5}{x} at the point (-2, \frac{-5}{2}) using the formula lim x->a \frac{f(x)-f(a)}{x-a}
    \frac{\frac{5}{x}-(-\frac{5}{2})}{x-(-2)}

    i get two here and i am stuck
    \frac{\frac{5}{x}+(\frac{5}{2})}{x+2}
    I can see that I can potentially cancel out the (x+2)but I am not sure.
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  2. #2
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    Re: tangent slope of f

    Quote Originally Posted by delgeezee View Post
    what is the tangent slope of the f(x)= \frac{5}{x} at the point (-2, \frac{-5}{2}) using the formula lim x->a \frac{f(x)-f(a)}{x-a}
    \frac{\frac{5}{x}-(-\frac{5}{2})}{x-(-2)}

    i get two here and i am stuck
    \frac{\frac{5}{x}+(\frac{5}{2})}{x+2}
    I can see that I can potentially cancel out the (x+2)but I am not sure.
    The next step is

    \frac{\frac{10+5x}{2x}}{x+2}
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  3. #3
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    Re: tangent slope of f

    remember that (a/b)/c = (a/b)(1/c) = a/(bc), to simplify the fraction.

    does x+2 divide 10+5x evenly?
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