Question

can someone describe to me what an imaginary numbers are?

Answer 1

A number that does not belong to real domain is an imaginary number.
when you have a negative quantity under a square root sign, we come across an imaginary number.
like \(\sqrt{-1}=i\) is an imaginary number.
so is \(\sqrt{-9}=\sqrt{9}\sqrt{-1}=3i\)

Answer 2

imaginary numbers on the imaginary axis

Answer 3

\[\sqrt1=1,-1\]
\[\sqrt[4]1=1,-1,i,-i\]