Ask your own question, for FREE!
Mathematics 15 Online
OpenStudy (anonymous):

how do I find the derivative of the square root of x

OpenStudy (shamil98):

power rule. √x = x^1/2 f(x) = x^1/2 f'(x) = x^-1/2

OpenStudy (anonymous):

^ you forgot something f(x) = x^n f'(x) = nx^(n-1) So f'(x) in this case would be (1/2)x^(-1/2)

OpenStudy (shamil98):

oh yeah mb

OpenStudy (anonymous):

okay.. I guess I'm trying to do it the long way by taking the lim as h approaches 0 but ill do it like this

OpenStudy (anonymous):

thank you

OpenStudy (wolf1728):

The derivative of sqrt(x) or x^1/2 = 1/2•(x)•^-1/2•1 The 1 comes from the derivative of x

OpenStudy (anonymous):

I don't really see how limits are necessary here... \[\sqrt{x}\] is the same as\[x ^{1/2}\] and then you can just differentiate that easily.

OpenStudy (shamil98):

the definition of a derivative, i think that's what the person was using.

OpenStudy (shamil98):

instead of using the rules.

OpenStudy (wolf1728):

I think I'm right. Here's a page of my website: http://1728.org/chainrul.htm Scroll down to the bottom to see the derivative of a square root.

OpenStudy (anonymous):

yeah its way easier but this whole section they use lim so I figured I should too but thanks, I understand it :)

OpenStudy (anonymous):

Chain rule isn't necessary here, bro @wolf1728 . It's just x to the power of 0.5 There's no inside/outside functions. It's just x^0.5

OpenStudy (wolf1728):

Okay, anyway that derivative has been on my website for years and nobody has told me it's wrong. (although I could be).

OpenStudy (anonymous):

I'm not saying it's wrong, the chain rule still works, but it's not necessary. You're just multiplying the whole thing by 1 which doesn't change it. It would be necessary for eg (x^3)^1/2 or (x^2 + 8x)^1/2, formulas where multiple terms are square rooted but for a single term x^1/2 it won't change anything.

OpenStudy (anonymous):

Also @wolf1728 while I'm here, the Google+ link on your website doesn't direct to your profile, just the user's dashboard.

OpenStudy (wolf1728):

okay mentallychallenged I agree. Just thought I'd offer another solution.

Can't find your answer? Make a FREE account and ask your own questions, OR help others and earn volunteer hours!

Join our real-time social learning platform and learn together with your friends!
Can't find your answer? Make a FREE account and ask your own questions, OR help others and earn volunteer hours!

Join our real-time social learning platform and learn together with your friends!