can 1=(-1)??? check this out

[monu2010]

1=1
1=sqrt[1]
1=sqrt[(-1)*(-1)]
1=sqrt[-1]*sqrt[-1]
1=iota*iota
1=iota^2
and iota raise to the power 2 is -1
therefore
1= -1

where i made a mistake?????
help me out