\sqrt{\text{-} 1}=Den[[Imagina¨raenheten∗Wordlist∗∣imagina¨raenheten]]ia¨rdefinieradsomdettalvarskvadrata¨rlikamed\text{-} 1,alltsa˚i^2 = \text{-} 1.Drarmanrotenurdettafa˚rmanlikheteni = \sqrt{\text{-} 1}.$