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Math Help - Find the limit (if it exists) coming from the left?

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    Find the limit (if it exists) coming from the left?

    Lim of x->25 coming from the left (square root of x )- 5/(x-25)
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    Quote Originally Posted by DeeEmEm View Post
    Lim of x->25 coming from the left (square root of x )- 5/(x-25)
    Substitute t = \sqrt{x}: \displaystyle \frac{\sqrt{x} - 5}{x - 25} = \frac{t - 5}{t^2 - 25}. Your job is to calculate the limit of this as t approaches 5.
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    Quote Originally Posted by DeeEmEm View Post
    Lim of x->25 coming from the left (square root of x )- 5/(x-25)
    If I were you I would seriously reconsider my use of brackets here.

    MrF has made a guess at what is meant, but you really really don't want to have to rely on his/our psychic abilities.

    CB
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    Re brackets: (sqrt x)- 5/(x- 25) would normally be intepreted (by myself, anyway) as
    \sqrt{x}- \frac{5}{x- 25}.

    By the way, while mr. fantastic's " t= \sqrt{x}" substitution is probably simplest you could also think of x- 25 as a "difference of squares", (\sqrt{x})^2- 5^2 so the problem becomes
    \lim_{x\to 25}\frac{\sqrt{x- 5}}{(\sqrt{x+ 5})(\sqrt{x- 5})}
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