# Thread: Help with complex numbers?

1. ## Help with complex numbers?

question 5 in the attached pdf..

Please explain.. I know you get to a point where it is the sq root of -11 but idk what to do after this . Please help

2. ## Re: Help with complex numbers?

\displaystyle \begin{align*} \sqrt{-11} = \sqrt{-1 \cdot 11} = \sqrt{-1} \cdot \sqrt{11} = i\sqrt{11} \end{align*}