# Derivative of a square root function ??

• Mar 25th 2008, 04:54 PM
kbgemini16
Derivative of a square root function ??
ok.. I don't have the proper symbols so please bear w/ me...

If I need to find the derivative of:

5 √x^2 - 2√x = ?

Note: 5 is the root it's inside the little V of the sqrt symbol

What is the derivative?

I know the first part is x^2/5 but I can't differentiate the second one.

• Mar 25th 2008, 05:22 PM
o_O
$f(x) = \sqrt[5]{x^{2}} + 2\sqrt{x}$

Note that: $a^{\frac{m}{n}} = \sqrt[n]{a^{m}} = \left(\sqrt[n]{a}\right)^{m}$

We get:
$f(x) = x^{\frac{2}{5}} + 2x^{\frac{1}{2}}$

Now use your power rules as you have learned in your pre-calc days.
• Mar 26th 2008, 05:33 AM
kbgemini16
Thanks a bunch
Thank you !!!! (Clapping)