# Square rooting a negative number

• September 24th 2013, 02:12 AM
asilvester635
Square rooting a negative number
Is this right????
• September 24th 2013, 02:58 AM
Plato
Re: Square rooting a negative number
Quote:

Originally Posted by asilvester635
Is this right????

You posted this in the Pre-University Algebra Forum.
That makes it difficult to know what level of mathematics you are doing.

In simple algebra, if $y$ is a real number then $y^2\ge 0$.
Thus $\sqrt{-3}$ does not exist.

But if you are doing advanced algebra and know that there is a complex number $i$ such that $i^2=-1$ then if $y^2=-3$ we have $y=\pm\sqrt3~i$.