Exponential/Logarithmic functions

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Homework Statement



Find the derivative of
y = sqrt(XX)



The Attempt at a Solution



I tried using the equation d/dx (ax) = ax * ln a

Is this even a right start? The square root kind of throws me off. I'm not sure if this is the right equation to use or not. I was told the answer was

Xx / (2*sqrt(Xx)) but I'm not even sure how to get there given the answer. any hints or help? :(
 
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x=e^log(x). So x^x=e^(log(x)*x). Try treating it that way. Your given equation is only valid for 'a' being a constant. You can handle the sqrt by either using the chain rule or just the rules of exponents. sqrt(x^x)=(x^x)^(1/2)=x^(x/2), right?
 
how about starting by writing as
y = \sqrt{x^x} = (x^x)^{\frac{1}{2}}

then simplify and consider taking the log of both sides and implicit differentiation
 
There are two things I don't understand about this problem. First, when finding the nth root of a number, there should in theory be n solutions. However, the formula produces n+1 roots. Here is how. The first root is simply ##\left(r\right)^{\left(\frac{1}{n}\right)}##. Then you multiply this first root by n additional expressions given by the formula, as you go through k=0,1,...n-1. So you end up with n+1 roots, which cannot be correct. Let me illustrate what I mean. For this...
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