complex number root solving

trying to use matlab to solve some complex numbers, as a basic example how does one command matlab to find all the roots of;

z^2 - i = 0

Answer 1

[Azzi Abdelmalek]

sols=roots([ 1 0 -i])

%or

sols=double(solve('z^2-i'))

Answer 2

[Salman Khalaf]

sols=roots([ 1 0 -i])