I see many people saying that the imaginary number squared is -1, like so:(adsbygoogle = window.adsbygoogle || []).push({});

i = sqrt(-1)

i^{2}= sqrt(-1)*sqrt(-1) = (sqrt(-1))^{2}= -1

But, what about this:

i^{2}= sqrt(-1)*sqrt(-1) = sqrt(-1*-1) = sqrt(1) = 1

Can someone please explain to me why i^{2}= -1ifthe above counter example is correct? If not, can someone explain why my counter example is incorrect? It seems like both are correct, but how can that be so?

Thank you

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# Why does i^2=-1?

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