set f = CircleMap | [.r,(r + 1).[;
set g = CircleMap | [.0 ,1.[;
A1:
dom (CircleMap | [.r,(r + 1).[) = [.r,(r + 1).[
by Lm19, RELAT_1:91;
A2:
dom (CircleMap | [.0 ,1.[) = [.0 ,1.[
by Lm19, RELAT_1:91;
let x, y be set ; :: according to FUNCT_1:def 8 :: thesis: ( not x in K1((CircleMap | [.r,(r + 1).[)) or not y in K1((CircleMap | [.r,(r + 1).[)) or not (CircleMap | [.r,(r + 1).[) . x = (CircleMap | [.r,(r + 1).[) . y or x = y )
assume that
A3:
x in dom (CircleMap | [.r,(r + 1).[)
and
A4:
y in dom (CircleMap | [.r,(r + 1).[)
and
A5:
(CircleMap | [.r,(r + 1).[) . x = (CircleMap | [.r,(r + 1).[) . y
; :: thesis: x = y
reconsider x = x, y = y as Real by A1, A3, A4;
set x1 = frac x;
set y1 = frac y;
A6:
frac x = x - [\x/]
by INT_1:def 6;
A7:
frac y = y - [\y/]
by INT_1:def 6;
( 0 <= frac x & frac x < 1 )
by INT_1:69;
then A8:
frac x in [.0 ,1.[
by XXREAL_1:3;
( 0 <= frac y & frac y < 1 )
by INT_1:69;
then A9:
frac y in [.0 ,1.[
by XXREAL_1:3;
A10:
( r <= x & x < r + 1 )
by A1, A3, XXREAL_1:3;
A11:
( r <= y & y < r + 1 )
by A1, A4, XXREAL_1:3;
A12: (CircleMap | [.r,(r + 1).[) . x =
CircleMap . x
by A3, FUNCT_1:70
.=
CircleMap . (x + (- [\x/]))
by Th32
.=
(CircleMap | [.0 ,1.[) . (frac x)
by A2, A6, A8, FUNCT_1:70
;
(CircleMap | [.r,(r + 1).[) . y =
CircleMap . y
by A4, FUNCT_1:70
.=
CircleMap . (y + (- [\y/]))
by Th32
.=
(CircleMap | [.0 ,1.[) . (frac y)
by A2, A7, A9, FUNCT_1:70
;
then
frac x = frac y
by A2, A5, A8, A9, A12, Lm25, FUNCT_1:def 8;
hence
x = y
by A10, A11, TOPREALA:7; :: thesis: verum