Solving One-Sided Limit: lim_{x\rightarrow4^{-}} \frac{\sqrt{x}-2}{x-4}

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Homework Statement


lim[tex]_{x\rightarrow4^{-}}[/tex] [tex]\frac{\sqrt{x}-2}{x-4}[/tex]


Homework Equations


Typical methods used in solving one-sided limit.


The Attempt at a Solution


I plug in something a little bit bigger than four, like 4.0000001 into x, and I get [tex]\frac{something a little less than zero}{something a little less than zero}[/tex] to equal 1. But the answer is 1/4. How is this so?
 
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Multiply both the top and the bottom by [tex]\sqrt{x}+2[/tex]. This is called "multiplying by the conjugate" and is pretty standard for dealing with limits involving square roots