I have come up with a simple "paradox" (obviously I am doing something wrong). Sorry I can't use latex:(adsbygoogle = window.adsbygoogle || []).push({});

(-1)/1=1/(-1), take square root of both sides, so sqrt((-1)/1)=sqrt(1/(-1))

use sqrt(a/b)=srt(a)/sqrt(b) *, so i/1=1/i, implies i squared =1.

I think the problem is the part marked *, but I'm not sure in what circumstances this is valid. Can anybody help?

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# What rule am I breaking here?

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