How do you solve the quadratic $z^{2} + 1 = 0$ $z^2+1=0$ using any method?

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Answer 1 · 2016-08-14T09:17:50

$\pm i$ $+-i$

Simplest way is to add $- 1$ $-1$ to both sides:

$z^{2} = - 1$ $z^2 = -1$

Take square roots:

$z = \pm \sqrt{- 1} = \pm \sqrt{i^{2}} = \pm i$ $z = +-sqrt(-1) = +-sqrt(i^2) = +-i$

How do you solve the quadratic z2+1=0z^2+1=0 using any method?