Derivative of x^(x^2) with Respect to x | Calculus Homework Help

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Homework Statement


Differentiate x^{x^2}, with respect to x


Homework Equations



\frac{d}{dx} (x^{x^2})


The Attempt at a Solution


I arrived at... (ready?)

(ta dah!): x^{x^2}.(2x.\ln(x)+x)

I'm pretty confident this is wrong...

I went y(x)=x^{x^2}, then took the natural logarithm of both sides

Since \ln(x^{x^2}) = x^2.\ln(x) and \frac{d}{d(y(x))} (ln (y(x))) = \frac{1}{y(x)}

I got:

\frac{1}{y(x)} . \frac{d(y(x))}{dx} = \frac{d}{dx} (x^2.\ln(x))

\frac{1}{y(x)} . \frac{d(y(x))}{dx} = 2x.\ln(x)+\frac{x^2}{x}

\frac{d(y(x))}{dx} = 2x.\ln(x)+\frac{x^2}{x} . x^{x^2} = x^{x^2}.(2x.\ln(x)+x)

As I said, I think this is wrong. I've been working through examples all day and figured I might be able to come back to it, and hopefully figure it out (that is my excuse, and I'm sticking with it! :smile:); but since I don't have easy access to a computer, I thought I might ask you guys now, and check back tomorrow to see if anyone has offered any help.
Thanks everyone.
 
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Eh I think that is right, though I did it in my head. It's easy if you write it as the exponential of (x^2)(ln x), from which you get the original expression times the derivative of (x^2)(ln x) which by the product rule is 2x(ln x) + x.
 
I don't see why you think this would be wrong, because it's not.
 
Yup, I think it's pretty correct.
 
Snipez90, Cyosis & Karkas: Thankyou.
The question was from a multiple choice "quiz" that I saw, and I just didn't recognise the answer that I got (above) from being one of the possibilities: that's why I thought it was wrong. But it seems its not! Thanks for the responses everyone!
 
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