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# i as the principal root of -1

The formal definition of i is i^2=-1 and not √-1=i, and there's a good reason for this (although it's a bit technical). See Sal explain why. Created by Sal Khan.

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# i as the principal root of -1

Current time: 0:00Total duration: 6:44

0 energy points

The formal definition of i is i^2=-1 and not √-1=i, and there's a good reason for this (although it's a bit technical). See Sal explain why. Created by Sal Khan.