Apparently there is an isomorphism between the additive group [itex](ℝ,+)[/itex] of real numbers and the multiplicative group [itex](ℝ_{>0},×)[/itex] of positive real numbers.(adsbygoogle = window.adsbygoogle || []).push({});

But I thought that the reals were uncountably infinite and so don't understand how you could define a bijection between them?!

Thanks for your help!

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# Isomorphism between groups of real numbers

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