Question

x^2 + 1 = 0

Answer 1

This equation can't be solved into the real field.
So there is no solution.
Nevertheless, we find a solution in the complex field which is:
\[i^2 = -1 \rightarrow x1= i , x2= -1\]

Answer 2

hmm... very different approach to it, thankyou :)

Answer 3

x2 = -i, sorry, typo :) And you're welcome.

Answer 4

x = i

Answer 5

RAWR is cute! ^_^

Answer 6

x=±i