Help Needed: Explaining x^{x} = e^{xlgx} and x^{a}

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pamparana
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Hello,

I am having trouble getting my head around this:

Can someone explain why
[tex]x^{x}[/tex] = [tex]e^{xlgx}[/tex]

I cannot seem to understand why this is true. I am quite weak when it comes to handling exponentials. I dare say that I am terrified of e!

Also, would this also hold for a static power: so [tex]x^{a}[/tex]

Thanks,

Luca
 
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Remember that for a > 0, [tex]\ln ( a^b ) = b \ln a[/tex] and the fact that exponentation and the natural logarithm are inverse functions.
 
That makes sense!

Many thanks!