Question 265813
x^2+1 = 0 has no solution in the real number system.
If x^2 = -1
x = +-i
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So "i" is one solution for the equation x^2+1 = 0
But (sqrt(-1))^2 = -1
So (sqrt(-1))^2 + 1 = 0
Therefore sqrt(-1) = i
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For more on this subject use Google and
search for complex numbers.
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Completing the Square.
I would suggest you post one or two of the
problems you are having with this topic
as there are different ways of handling
simple and complex cases.
Cheers,
Stan H.