consider P1, P2 being non empty Subset of (TOP-REAL 2) such that
A1:
( P1 is being_S-P_arc & P2 is being_S-P_arc & R^2-unit_square = P1 \/ P2 )
by TOPREAL1:34;
consider f being Function of I[01] ,((TOP-REAL 2) | P1) such that
A2:
f is being_homeomorphism
by A1, TOPREAL1:36;
A3:
f is continuous
by A2, TOPS_2:def 5;
consider f0 being Function of I[01] ,((TOP-REAL 2) | P2) such that
A4:
f0 is being_homeomorphism
by A1, TOPREAL1:36;
A5:
f0 is continuous
by A4, TOPS_2:def 5;
A6:
I[01] is compact
by HEINE:11, TOPMETR:27;
A7:
rng f = [#] ((TOP-REAL 2) | P1)
by A2, TOPS_2:def 5;
reconsider P1 = P1 as non empty Subset of (TOP-REAL 2) ;
(TOP-REAL 2) | P1 is compact
by A3, A6, A7, COMPTS_1:23;
then A8:
P1 is compact
by COMPTS_1:12;
A9:
rng f0 = [#] ((TOP-REAL 2) | P2)
by A4, TOPS_2:def 5;
reconsider P2 = P2 as non empty Subset of (TOP-REAL 2) ;
(TOP-REAL 2) | P2 is compact
by A5, A6, A9, COMPTS_1:23;
then
P2 is compact
by COMPTS_1:12;
hence
R^2-unit_square is compact
by A1, A8, COMPTS_1:19; :: thesis: verum