(adsbygoogle = window.adsbygoogle || []).push({}); Theorem 1.21 Rudin. Obviously wrongly stated, right?

Theorem 1.21 in Rudin states:

For every real [itex]x > 0[/itex], and every integer [itex]n > 0[/itex], there is one andonly one real[itex]y[/itex] such that [itex]y^{n} = x[/itex].

The bold part should be "only onepositivereal", shouldn't it, or am I missing something? The proof also start with with an implicit assumption that [itex]y[/itex] is positive.

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# Theorem 1.21 Rudin. Obviously wrong stated, right?

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