# What's the derivative of {sqrt (2x)} ?

#### urbantrained

I'm told that you don't need the product rule, or chain rule, or quotient rule to work it out. Can anyone show the workings as well please...???

#### HallsofIvy

Homework Helper
I don't see anyway to find the derivative of &radic;(2x) without using the chain rule (because of the "2", not the "&radic;").

Write f(x)= (2x)1/2 and use the "power" rule:

f'(x)= (1/2)(2x)1/2-1(2x)'
= (1/2)(2x)-1/2(2)

#### Hurkyl

Staff Emeritus
Gold Member

You can take it from here using the power rule and the scalar multiple rule.

#### chroot

Staff Emeritus
Gold Member
I love when you to Alfred E. Newmans fight it out.

- Warren

Staff Emeritus
Gold Member

#### HallsofIvy

Homework Helper
Hurkyl
ã(2x) = ã2 ãx

You can take it from here using the power rule and the scalar multiple rule.
Oh, well, if want to do it the EASY way!

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