Simplifying Limit (1/sqrtx - 1/2)/(x-4) | Step-by-Step Solution Explained

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To solve the limit lim (1/sqrt(x) - 1/2)/(x-4) as x approaches 4, l'Hôpital's rule is recommended as an effective method. Alternatively, the expression can be rewritten as (1/sqrt(x) - 1/2)/((sqrt(x)-2)(sqrt(x)+2)) to simplify the calculation. This approach clarifies the behavior of the function near the limit point. The final answer is confirmed to be -1/16. Understanding these techniques is essential for tackling similar limit problems.
RadiationX
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For the life of me I can't figure this limit out

lim ( 1/sqt x - 1/2)/ ( X -4)
x->4


I KNOW THE ANSWER IS -1/16 BUT WHAT ARE THE STEPS NECESSARY TO REACH THIS SOLUTION?
THANKS FOR ANY HELP.
 
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Try l'Hopital's rule- it works!
 
Another way (if I understand your problem correctly) would be to rewrite the given function as

\frac{\frac{1}{\sqrt{x}} - \frac{1}{2}}{(\sqrt{x}-2)(\sqrt{x}+2)}

if you're not familiar with L-Hospital's Theorem.

Cheers
Vivek
 
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