Limit of a Function with Radicals in the Numerator

cphill29
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Homework Statement



Limit as h approaches 0 for [rad(5+h)-rad(5-h)]/h

Homework Equations


The Attempt at a Solution



limit as h approaches 0 for [(5+h)-(5-h)]/h[rad(5+h)+rad(5-h)]

limit as h approaches 0 for 2h/h[rad(5+h)+rad(5-h)]

limit as h approaches 0 for h/[rad(5+h)+rad(5-h)]

This was as far as I could get. Sorry if it's a little messy.
 
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Limit as h approaches 0 for [rad(5+h)-rad(5-h)]/h

That is Lim_(h to 0) \frac{\sqrt{5+h} - \sqrt{5-h}}{h}

Multiply numerator and denominator by \sqrt{5+h} + \sqrt{5-h}
When you work through steps, you obtain expression,...
\frac{2}{\sqrt{5+h} + \sqrt{5-h}}

As h approaches 0, the expression approaches \frac{2}{\sqrt{5} + \sqrt{5}}

Simplifying to \frac{\sqrt{5}}{5}. DONE.

Note minor TEX/LATEX learning problems, "Lim as h approaches 0"
 
Thank you for clearing that up. Instead of cancelling the 'h', I canceled the 2 by mistake.
 
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