let y be set ; :: according to TARSKI:def 3 :: thesis: ( not y in rng ((R^1 (AffineMap (- 1),1)) | (R^1 ].0 ,1.[)) or y in ].0 ,1.[ )
assume
y in rng ((R^1 (AffineMap (- 1),1)) | (R^1 ].0 ,1.[))
; :: thesis: y in ].0 ,1.[
then consider x being set such that
A1:
x in dom ((R^1 (AffineMap (- 1),1)) | (R^1 ].0 ,1.[))
and
A2:
((R^1 (AffineMap (- 1),1)) | (R^1 ].0 ,1.[)) . x = y
by FUNCT_1:def 5;
reconsider x = x as Real by A1, Lm35;
A3: y =
(AffineMap (- 1),1) . x
by A1, A2, Lm35, FUNCT_1:72
.=
((- 1) * x) + 1
by JORDAN16:def 3
;
( 0 < x & x < 1 )
by A1, Lm35, XXREAL_1:4;
then
( 1 - 1 < 1 - x & 1 - x < 1 - 0 )
by XREAL_1:17;
hence
y in ].0 ,1.[
by A3, XXREAL_1:4; :: thesis: verum