Why we write sq rt(-2) ?

1 Answer
May 8, 2018

See explanation below

Explanation:

#sqrt(-2)# is not a real number because there is no number x such that #x^2=-2#

We are dealing with complex numbers. By definition there is a number called #i# (imaginary unit) defined by #i^2=-1#

We can write then #sqrt(-2)=sqrt(2·(-1))=sqrt2i#