In the first part of the question I've proved that :
The boundary of the square that its vertex are: (0,1) , (1,1), (1,0), (0,0)
is homeomorphic to the unit circle (x^2+y^2=1) as sub-spaces of R^2.
Now I need to prove that the unit circle (as a sub-space of R^2) is not homeomorphic to [0,1] as a sub-space of Rs (Sorgenfrey's line...)
HELP IS NEEDED !
TNX a lot!