let p1, p2 be Point of (TOP-REAL 2); :: thesis: for P being non empty compact Subset of (TOP-REAL 2) st P = { p where p is Point of (TOP-REAL 2) : |.p.| = 1 } & LE p1,p2,P & p1 <> p2 & p1 `1 < 0 & p2 `1 < 0 & p1 `2 < 0 & p2 `2 < 0 holds
( p1 `1 > p2 `1 & p1 `2 < p2 `2 )
let P be non empty compact Subset of (TOP-REAL 2); :: thesis: ( P = { p where p is Point of (TOP-REAL 2) : |.p.| = 1 } & LE p1,p2,P & p1 <> p2 & p1 `1 < 0 & p2 `1 < 0 & p1 `2 < 0 & p2 `2 < 0 implies ( p1 `1 > p2 `1 & p1 `2 < p2 `2 ) )
assume A1:
( P = { p where p is Point of (TOP-REAL 2) : |.p.| = 1 } & LE p1,p2,P & p1 <> p2 & p1 `1 < 0 & p2 `1 < 0 & p1 `2 < 0 & p2 `2 < 0 )
; :: thesis: ( p1 `1 > p2 `1 & p1 `2 < p2 `2 )
then
P is being_simple_closed_curve
by JGRAPH_3:36;
then A2:
( p1 in P & p2 in P )
by A1, JORDAN7:5;
A3:
Upper_Arc P = { p where p is Point of (TOP-REAL 2) : ( p in P & p `2 >= 0 ) }
by A1, Th37;
then A5:
( p1 in Lower_Arc P & p2 in Lower_Arc P & not p2 = W-min P & LE p1,p2, Lower_Arc P, E-max P, W-min P )
by A1, JORDAN6:def 10;
consider f being Function of I[01] ,((TOP-REAL 2) | (Lower_Arc P)) such that
A6:
( f is being_homeomorphism & ( for q1, q2 being Point of (TOP-REAL 2)
for r1, r2 being Real st f . r1 = q1 & f . r2 = q2 & r1 in [.0 ,1.] & r2 in [.0 ,1.] holds
( r1 < r2 iff q1 `1 > q2 `1 ) ) & f . 0 = E-max P & f . 1 = W-min P )
by A1, Th45;
A7: rng f =
[#] ((TOP-REAL 2) | (Lower_Arc P))
by A6, TOPS_2:def 5
.=
Lower_Arc P
by PRE_TOPC:def 10
;
then consider x1 being set such that
A8:
( x1 in dom f & p1 = f . x1 )
by A5, FUNCT_1:def 5;
consider x2 being set such that
A9:
( x2 in dom f & p2 = f . x2 )
by A5, A7, FUNCT_1:def 5;
A10: dom f =
[#] I[01]
by A6, TOPS_2:def 5
.=
[.0 ,1.]
by BORSUK_1:83
;
then reconsider r11 = x1 as Real by A8;
reconsider r22 = x2 as Real by A9, A10;
A11:
( 0 <= r11 & r11 <= 1 )
by A8, A10, XXREAL_1:1;
A12:
( 0 <= r22 & r22 <= 1 )
by A9, A10, XXREAL_1:1;
A13:
( r11 < r22 iff p1 `1 > p2 `1 )
by A6, A8, A9, A10;
A14:
r11 <= r22
by A5, A6, A8, A9, A11, A12, JORDAN5C:def 3;
consider p3 being Point of (TOP-REAL 2) such that
A15:
( p3 = p1 & |.p3.| = 1 )
by A1, A2;
1 ^2 = ((p1 `1 ) ^2 ) + ((p1 `2 ) ^2 )
by A15, JGRAPH_3:10;
then A16:
(1 ^2 ) - ((p1 `1 ) ^2 ) = (- (p1 `2 )) ^2
;
A17:
- (p1 `1 ) > 0
by A1, XREAL_1:60;
- (p1 `2 ) > 0
by A1, XREAL_1:60;
then
- (p1 `2 ) = sqrt ((1 ^2 ) - ((- (p1 `1 )) ^2 ))
by A16, SQUARE_1:89;
then A18:
p1 `2 = - (sqrt ((1 ^2 ) - ((- (p1 `1 )) ^2 )))
;
consider p4 being Point of (TOP-REAL 2) such that
A19:
( p4 = p2 & |.p4.| = 1 )
by A1, A2;
A20:
1 ^2 = ((p2 `1 ) ^2 ) + ((p2 `2 ) ^2 )
by A19, JGRAPH_3:10;
then A21:
(1 ^2 ) - ((p2 `1 ) ^2 ) = (- (p2 `2 )) ^2
;
- (p2 `2 ) > 0
by A1, XREAL_1:60;
then
- (p2 `2 ) = sqrt ((1 ^2 ) - ((- (p2 `1 )) ^2 ))
by A21, SQUARE_1:89;
then A22:
p2 `2 = - (sqrt ((1 ^2 ) - ((- (p2 `1 )) ^2 )))
;
- (p1 `1 ) < - (p2 `1 )
by A1, A8, A9, A13, A14, XREAL_1:26, XXREAL_0:1;
then
(- (p1 `1 )) ^2 < (- (p2 `1 )) ^2
by A17, SQUARE_1:78;
then
(1 ^2 ) - ((- (p1 `1 )) ^2 ) > (1 ^2 ) - ((- (p2 `1 )) ^2 )
by XREAL_1:17;
then
sqrt ((1 ^2 ) - ((- (p1 `1 )) ^2 )) > sqrt ((1 ^2 ) - ((- (p2 `1 )) ^2 ))
by A20, SQUARE_1:95, XREAL_1:65;
hence
( p1 `1 > p2 `1 & p1 `2 < p2 `2 )
by A8, A9, A13, A14, A18, A22, XREAL_1:26, XXREAL_0:1; :: thesis: verum