If anybody knows could they please tell me how it is known that there exists some number 'e' with the property that the derivative of e(adsbygoogle = window.adsbygoogle || []).push({}); ^{x}is itself.

I have a feeling this might require some definition of a^{b}.

Surely this isn't a complicated problem, but for some reason I can't work it out or even find a good answer online.

Thanks for the help.

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# Proof for exponential number

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