My analysis text defines inverse functions only for bijections.(adsbygoogle = window.adsbygoogle || []).push({});

But [itex] y = e^{x} [/itex] is not bijective, so according to my book it's inverse ([itex] ln x [/itex]) wouldn't be defined? Am I missing something or is my textbook just plain wrong?

I use the text by Bartle and Sherbert.

Thanks!

BiP

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# Function must be a bijection for its inverse to exist?

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