thus
CircleMap r is one-to-one
; :: thesis: ( CircleMap r is onto & CircleMap r is continuous )
thus
CircleMap r is onto
:: thesis: CircleMap r is continuous proof
set A =
].r,(r + 1).[;
set f =
CircleMap | ].r,(r + 1).[;
set TOUC =
Topen_unit_circle (CircleMap . r);
set X = the
carrier of
(Topen_unit_circle (CircleMap . r));
thus
rng (CircleMap r) c= the
carrier of
(Topen_unit_circle (CircleMap . r))
;
:: according to XBOOLE_0:def 10,
FUNCT_2:def 3 :: thesis: the carrier of (Topen_unit_circle (CircleMap . r)) c= rng (CircleMap r)
let y be
set ;
:: according to TARSKI:def 3 :: thesis: ( not y in the carrier of (Topen_unit_circle (CircleMap . r)) or y in rng (CircleMap r) )
assume A1:
y in the
carrier of
(Topen_unit_circle (CircleMap . r))
;
:: thesis: y in rng (CircleMap r)
then reconsider z =
y as
Point of
(TOP-REAL 2) by Lm9;
set z1 =
z `1 ;
set z2 =
z `2 ;
set x =
(arccos (z `1 )) / (2 * PI );
A2:
[\r/] <= r
by INT_1:def 4;
A3:
dom (CircleMap | ].r,(r + 1).[) = ].r,(r + 1).[
by Lm19, RELAT_1:91;
z is
Point of
(Tunit_circle 2)
by A1, PRE_TOPC:55;
then A4:
|.z.| = 1
by Th12;
A5:
((z `1 ) ^2 ) + ((z `2 ) ^2 ) = |.z.| ^2
by JGRAPH_1:46;
A6:
(
- 1
<= z `1 &
z `1 <= 1 )
by A1, Th27;
then A7:
0 <= (arccos (z `1 )) / (2 * PI )
by Lm24;
(arccos (z `1 )) / (2 * PI ) <= 1
/ 2
by A6, Lm24;
then A8:
(arccos (z `1 )) / (2 * PI ) < 1
by XXREAL_0:2;
then A9:
((arccos (z `1 )) / (2 * PI )) - ((arccos (z `1 )) / (2 * PI )) < 1
- ((arccos (z `1 )) / (2 * PI ))
by XREAL_1:16;
per cases
( z `2 < 0 or z `2 >= 0 )
;
suppose A10:
z `2 < 0
;
:: thesis: y in rng (CircleMap r)A11:
CircleMap . (- ((arccos (z `1 )) / (2 * PI ))) =
|[(cos (- ((2 * PI ) * ((arccos (z `1 )) / (2 * PI ))))),(sin ((2 * PI ) * (- ((arccos (z `1 )) / (2 * PI )))))]|
by Def11
.=
|[(cos ((2 * PI ) * ((arccos (z `1 )) / (2 * PI )))),(sin ((2 * PI ) * (- ((arccos (z `1 )) / (2 * PI )))))]|
by SIN_COS:34
.=
|[(cos (arccos (z `1 ))),(sin (- ((2 * PI ) * ((arccos (z `1 )) / (2 * PI )))))]|
by XCMPLX_1:88
.=
|[(cos (arccos (z `1 ))),(- (sin ((2 * PI ) * ((arccos (z `1 )) / (2 * PI )))))]|
by SIN_COS:34
.=
|[(cos (arccos (z `1 ))),(- (sin (arccos (z `1 ))))]|
by XCMPLX_1:88
.=
|[(z `1 ),(- (sin (arccos (z `1 ))))]|
by A6, SIN_COS6:93
.=
|[(z `1 ),(- (- (z `2 )))]|
by A4, A5, A10, SIN_COS6:105
.=
y
by EUCLID:57
;
per cases
( (1 - ((arccos (z `1 )) / (2 * PI ))) + [\r/] in ].r,(r + 1).[ or not (1 - ((arccos (z `1 )) / (2 * PI ))) + [\r/] in ].r,(r + 1).[ )
;
suppose A13:
not
(1 - ((arccos (z `1 )) / (2 * PI ))) + [\r/] in ].r,(r + 1).[
;
:: thesis: y in rng (CircleMap r)then
[\r/] - ((arccos (z `1 )) / (2 * PI )) < r - 0
by A2, A7, XREAL_1:17;
then
((- ((arccos (z `1 )) / (2 * PI ))) + [\r/]) + 1
< r + 1
by XREAL_1:8;
then A14:
r >= (1 - ((arccos (z `1 )) / (2 * PI ))) + [\r/]
by A13, XXREAL_1:4;
([\r/] + 1) + 0 < ([\r/] + 1) + (1 - ((arccos (z `1 )) / (2 * PI )))
by A9, XREAL_1:8;
then A16:
r < (2 - ((arccos (z `1 )) / (2 * PI ))) + [\r/]
by INT_1:52, XXREAL_0:2;
(1 - ((arccos (z `1 )) / (2 * PI ))) + [\r/] < r
by A14, A15, XXREAL_0:1;
then
((1 - ((arccos (z `1 )) / (2 * PI ))) + [\r/]) + 1
< r + 1
by XREAL_1:8;
then A17:
((- ((arccos (z `1 )) / (2 * PI ))) + [\r/]) + 2
in ].r,(r + 1).[
by A16, XXREAL_1:4;
then (CircleMap | ].r,(r + 1).[) . ((- ((arccos (z `1 )) / (2 * PI ))) + ([\r/] + 2)) =
CircleMap . ((- ((arccos (z `1 )) / (2 * PI ))) + ([\r/] + 2))
by FUNCT_1:72
.=
CircleMap . (- ((arccos (z `1 )) / (2 * PI )))
by Th32
;
hence
y in rng (CircleMap r)
by A3, A11, A17, FUNCT_1:def 5;
:: thesis: verum end; end; end; suppose A18:
z `2 >= 0
;
:: thesis: y in rng (CircleMap r)A19:
CircleMap . ((arccos (z `1 )) / (2 * PI )) =
|[(cos ((2 * PI ) * ((arccos (z `1 )) / (2 * PI )))),(sin ((2 * PI ) * ((arccos (z `1 )) / (2 * PI ))))]|
by Def11
.=
|[(cos (arccos (z `1 ))),(sin ((2 * PI ) * ((arccos (z `1 )) / (2 * PI ))))]|
by XCMPLX_1:88
.=
|[(cos (arccos (z `1 ))),(sin (arccos (z `1 )))]|
by XCMPLX_1:88
.=
|[(z `1 ),(sin (arccos (z `1 )))]|
by A6, SIN_COS6:93
.=
|[(z `1 ),(z `2 )]|
by A4, A5, A18, SIN_COS6:104
.=
y
by EUCLID:57
;
per cases
( ((arccos (z `1 )) / (2 * PI )) + [\r/] in ].r,(r + 1).[ or not ((arccos (z `1 )) / (2 * PI )) + [\r/] in ].r,(r + 1).[ )
;
suppose A21:
not
((arccos (z `1 )) / (2 * PI )) + [\r/] in ].r,(r + 1).[
;
:: thesis: y in rng (CircleMap r)
0 + ([\r/] + 1) <= ((arccos (z `1 )) / (2 * PI )) + ([\r/] + 1)
by A7, XREAL_1:8;
then A22:
r < (((arccos (z `1 )) / (2 * PI )) + [\r/]) + 1
by INT_1:52, XXREAL_0:2;
((arccos (z `1 )) / (2 * PI )) + [\r/] < 1
+ r
by A2, A8, XREAL_1:10;
then
((arccos (z `1 )) / (2 * PI )) + [\r/] <= r
by A21, XXREAL_1:4;
then A23:
(((arccos (z `1 )) / (2 * PI )) + [\r/]) + 1
<= r + 1
by XREAL_1:8;
then
(((arccos (z `1 )) / (2 * PI )) + [\r/]) + 1
< r + 1
by A23, XXREAL_0:1;
then A24:
(((arccos (z `1 )) / (2 * PI )) + [\r/]) + 1
in ].r,(r + 1).[
by A22, XXREAL_1:4;
then (CircleMap | ].r,(r + 1).[) . ((((arccos (z `1 )) / (2 * PI )) + [\r/]) + 1) =
CircleMap . (((arccos (z `1 )) / (2 * PI )) + ([\r/] + 1))
by FUNCT_1:72
.=
CircleMap . ((arccos (z `1 )) / (2 * PI ))
by Th32
;
hence
y in rng (CircleMap r)
by A3, A19, A24, FUNCT_1:def 5;
:: thesis: verum end; end; end; end;
end;
Topen_unit_circle (CircleMap . r) = (Tunit_circle 2) | (([#] (Tunit_circle 2)) \ {(CircleMap . r)})
by Th23;
hence
CircleMap r is continuous
by TOPREALA:29; :: thesis: verum