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How do we find $$\lim_{x \to 0^{+}} (x^{x^{x}} - x^x)??$$ The answer given is equal to $-1$. Any help is appreciated.

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    Hint: what is $\lim\limits_{x\to 0^+}x^x$?2017-01-26
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    This pdf might help you...[limits of x^x^x......^x](http://www.ww.ingeniousmathstat.org/sites/default/files/J09727._Marshall_Ash.pdf)2017-01-26

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Write $$ x^{x^x}=e^{x^x\log x}=e^{e^{x\log x}\log x}$$ and

$$x^x=e^{x\log x}$$ thus the limit become

$$\lim_{x\rightarrow 0^+}\Big( e^{e^{x\log x}\log x}\space -\space e^{x\log x}\Big)=\lim_{x\rightarrow 0^+}e^{e^{x\log x}\log x}-\lim_{x\rightarrow 0^+}e^{x\log x}$$

Now it easy to see that the first limit is $0$ and second is $1$; thus the different is exactly $-1$.

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    That was really helpful2017-01-27