Finding derivative from limit definition

**AMaccy** · May 29th 2009, 08:05 PM

Given the limit definition :

$m= \lim_{\Delta x\rightarrow 0} f(x) = (x+\Delta x)- f(x) / \Delta x$

( / means all divided by $\Delta x$ ) how can I find the derivative of:

$f(x) = \sqrt{x+2}$

Step by step would be helpful.

**Calculus26** · May 29th 2009, 08:28 PM

See attachment

**Random Variable** · May 29th 2009, 08:40 PM

$\lim_{\Delta x\rightarrow 0} \frac {\sqrt{(x+\Delta x)+2} - \sqrt {x+2}}{\Delta x}$

$= \lim_{\Delta x\rightarrow 0} \frac {\sqrt{(x+\Delta x)+2} - \sqrt {x+2}}{\Delta x} \frac {\sqrt {(x+\Delta x)+2} + \sqrt {x+2}}{\sqrt{(x+\Delta x)+2}+ \sqrt {x+2}}$

and go from there

Thread: Finding derivative from limit definition

LinkBack

Thread Tools

Display

Finding derivative from limit definition

Similar Math Help Forum Discussions

[SOLVED] limit definition of derivative

Using Definition Of Derivative As A Limit to Calculate...

limit definition of a derivative?

Limit definition and derivative

derivative using limit definition

Search Tags