let f be PartFunc of [:RNS_Real,RNS_Real:],RNS_Real; for g being PartFunc of [:REAL,REAL:],REAL
for t being Element of REAL st f is_uniformly_continuous_on dom f & f = g holds
( ProjPMap1 (g,t) is uniformly_continuous & ProjPMap2 (g,t) is uniformly_continuous )
let g be PartFunc of [:REAL,REAL:],REAL; for t being Element of REAL st f is_uniformly_continuous_on dom f & f = g holds
( ProjPMap1 (g,t) is uniformly_continuous & ProjPMap2 (g,t) is uniformly_continuous )
let t be Element of REAL ; ( f is_uniformly_continuous_on dom f & f = g implies ( ProjPMap1 (g,t) is uniformly_continuous & ProjPMap2 (g,t) is uniformly_continuous ) )
assume that
A1:
f is_uniformly_continuous_on dom f
and
A2:
f = g
; ( ProjPMap1 (g,t) is uniformly_continuous & ProjPMap2 (g,t) is uniformly_continuous )
for r being Real st 0 < r holds
ex s being Real st
( 0 < s & ( for y1, y2 being Real st y1 in dom (ProjPMap1 (g,t)) & y2 in dom (ProjPMap1 (g,t)) & |.(y1 - y2).| < s holds
|.(((ProjPMap1 (g,t)) . y1) - ((ProjPMap1 (g,t)) . y2)).| < r ) )
proof
let r be
Real;
( 0 < r implies ex s being Real st
( 0 < s & ( for y1, y2 being Real st y1 in dom (ProjPMap1 (g,t)) & y2 in dom (ProjPMap1 (g,t)) & |.(y1 - y2).| < s holds
|.(((ProjPMap1 (g,t)) . y1) - ((ProjPMap1 (g,t)) . y2)).| < r ) ) )
assume
0 < r
;
ex s being Real st
( 0 < s & ( for y1, y2 being Real st y1 in dom (ProjPMap1 (g,t)) & y2 in dom (ProjPMap1 (g,t)) & |.(y1 - y2).| < s holds
|.(((ProjPMap1 (g,t)) . y1) - ((ProjPMap1 (g,t)) . y2)).| < r ) )
then consider s being
Real such that A3:
0 < s
and A4:
for
p1,
p2 being
Point of
[:RNS_Real,RNS_Real:] st
p1 in dom f &
p2 in dom f &
||.(p1 - p2).|| < s holds
||.((f /. p1) - (f /. p2)).|| < r
by A1;
now for y1, y2 being Real st y1 in dom (ProjPMap1 (g,t)) & y2 in dom (ProjPMap1 (g,t)) & |.(y1 - y2).| < s holds
|.(((ProjPMap1 (g,t)) . y1) - ((ProjPMap1 (g,t)) . y2)).| < rlet y1,
y2 be
Real;
( y1 in dom (ProjPMap1 (g,t)) & y2 in dom (ProjPMap1 (g,t)) & |.(y1 - y2).| < s implies |.(((ProjPMap1 (g,t)) . y1) - ((ProjPMap1 (g,t)) . y2)).| < r )assume that A5:
y1 in dom (ProjPMap1 (g,t))
and A6:
y2 in dom (ProjPMap1 (g,t))
and A7:
|.(y1 - y2).| < s
;
|.(((ProjPMap1 (g,t)) . y1) - ((ProjPMap1 (g,t)) . y2)).| < rA8:
X-section (
(dom g),
t)
= { y where y is Element of REAL : [t,y] in dom g }
by MEASUR11:def 4;
A9:
(
y1 in X-section (
(dom g),
t) &
y2 in X-section (
(dom g),
t) )
by A5, A6, MESFUN12:def 3;
then A10:
ex
y being
Element of
REAL st
(
y = y1 &
[t,y] in dom g )
by A8;
A11:
ex
y being
Element of
REAL st
(
y = y2 &
[t,y] in dom g )
by A8, A9;
reconsider xx =
t as
Point of
RNS_Real ;
reconsider yy1 =
y1 as
Point of
RNS_Real by XREAL_0:def 1;
reconsider yy2 =
y2 as
Point of
RNS_Real by XREAL_0:def 1;
reconsider p1 =
[xx,yy1] as
Point of
[:RNS_Real,RNS_Real:] ;
reconsider p2 =
[xx,yy2] as
Point of
[:RNS_Real,RNS_Real:] ;
A12:
yy1 - yy2 = y1 - y2
by DUALSP03:4;
p1 - p2 = [xx,yy1] + [(- xx),(- yy2)]
by PRVECT_3:18;
then
p1 - p2 = [(xx - xx),(yy1 - yy2)]
by PRVECT_3:18;
then
p1 - p2 = [(0. RNS_Real),(yy1 - yy2)]
by RLVECT_1:15;
then
||.(p1 - p2).|| = sqrt ((||.(0. RNS_Real).|| ^2) + (||.(yy1 - yy2).|| ^2))
by NDIFF_8:1;
then
||.(p1 - p2).|| = ||.(yy1 - yy2).||
by SQUARE_1:22;
then
||.(p1 - p2).|| = |.(y1 - y2).|
by A12, EUCLID:def 2;
then A13:
||.((f /. p1) - (f /. p2)).|| < r
by A4, A7, A2, A10, A11;
(
(ProjPMap1 (g,t)) . y1 = g . (
t,
y1) &
(ProjPMap1 (g,t)) . y2 = g . (
t,
y2) )
by A10, A11, MESFUN12:def 3;
then
(
(ProjPMap1 (g,t)) . y1 = f /. p1 &
(ProjPMap1 (g,t)) . y2 = f /. p2 )
by A2, A10, A11, PARTFUN1:def 6;
then
((ProjPMap1 (g,t)) . y1) - ((ProjPMap1 (g,t)) . y2) = (f /. p1) - (f /. p2)
by DUALSP03:4;
hence
|.(((ProjPMap1 (g,t)) . y1) - ((ProjPMap1 (g,t)) . y2)).| < r
by A13, EUCLID:def 2;
verum end;
hence
ex
s being
Real st
(
0 < s & ( for
y1,
y2 being
Real st
y1 in dom (ProjPMap1 (g,t)) &
y2 in dom (ProjPMap1 (g,t)) &
|.(y1 - y2).| < s holds
|.(((ProjPMap1 (g,t)) . y1) - ((ProjPMap1 (g,t)) . y2)).| < r ) )
by A3;
verum
end;
hence
ProjPMap1 (g,t) is uniformly_continuous
by FCONT_2:def 1; ProjPMap2 (g,t) is uniformly_continuous
for r being Real st 0 < r holds
ex s being Real st
( 0 < s & ( for x1, x2 being Real st x1 in dom (ProjPMap2 (g,t)) & x2 in dom (ProjPMap2 (g,t)) & |.(x1 - x2).| < s holds
|.(((ProjPMap2 (g,t)) . x1) - ((ProjPMap2 (g,t)) . x2)).| < r ) )
proof
let r be
Real;
( 0 < r implies ex s being Real st
( 0 < s & ( for x1, x2 being Real st x1 in dom (ProjPMap2 (g,t)) & x2 in dom (ProjPMap2 (g,t)) & |.(x1 - x2).| < s holds
|.(((ProjPMap2 (g,t)) . x1) - ((ProjPMap2 (g,t)) . x2)).| < r ) ) )
assume
0 < r
;
ex s being Real st
( 0 < s & ( for x1, x2 being Real st x1 in dom (ProjPMap2 (g,t)) & x2 in dom (ProjPMap2 (g,t)) & |.(x1 - x2).| < s holds
|.(((ProjPMap2 (g,t)) . x1) - ((ProjPMap2 (g,t)) . x2)).| < r ) )
then consider s being
Real such that A14:
0 < s
and A15:
for
p1,
p2 being
Point of
[:RNS_Real,RNS_Real:] st
p1 in dom f &
p2 in dom f &
||.(p1 - p2).|| < s holds
||.((f /. p1) - (f /. p2)).|| < r
by A1;
now for x1, x2 being Real st x1 in dom (ProjPMap2 (g,t)) & x2 in dom (ProjPMap2 (g,t)) & |.(x1 - x2).| < s holds
|.(((ProjPMap2 (g,t)) . x1) - ((ProjPMap2 (g,t)) . x2)).| < rlet x1,
x2 be
Real;
( x1 in dom (ProjPMap2 (g,t)) & x2 in dom (ProjPMap2 (g,t)) & |.(x1 - x2).| < s implies |.(((ProjPMap2 (g,t)) . x1) - ((ProjPMap2 (g,t)) . x2)).| < r )assume that A16:
x1 in dom (ProjPMap2 (g,t))
and A17:
x2 in dom (ProjPMap2 (g,t))
and A18:
|.(x1 - x2).| < s
;
|.(((ProjPMap2 (g,t)) . x1) - ((ProjPMap2 (g,t)) . x2)).| < rA19:
Y-section (
(dom g),
t)
= { x where x is Element of REAL : [x,t] in dom g }
by MEASUR11:def 5;
A20:
(
x1 in Y-section (
(dom g),
t) &
x2 in Y-section (
(dom g),
t) )
by A16, A17, MESFUN12:def 4;
then A21:
ex
x being
Element of
REAL st
(
x = x1 &
[x,t] in dom g )
by A19;
A22:
ex
x being
Element of
REAL st
(
x = x2 &
[x,t] in dom g )
by A19, A20;
reconsider yy =
t as
Point of
RNS_Real ;
reconsider xx1 =
x1 as
Point of
RNS_Real by XREAL_0:def 1;
reconsider xx2 =
x2 as
Point of
RNS_Real by XREAL_0:def 1;
reconsider p1 =
[xx1,yy] as
Point of
[:RNS_Real,RNS_Real:] ;
reconsider p2 =
[xx2,yy] as
Point of
[:RNS_Real,RNS_Real:] ;
A23:
xx1 - xx2 = x1 - x2
by DUALSP03:4;
p1 - p2 = [xx1,yy] + [(- xx2),(- yy)]
by PRVECT_3:18;
then
p1 - p2 = [(xx1 - xx2),(yy - yy)]
by PRVECT_3:18;
then
p1 - p2 = [(xx1 - xx2),(0. RNS_Real)]
by RLVECT_1:15;
then
||.(p1 - p2).|| = sqrt ((||.(0. RNS_Real).|| ^2) + (||.(xx1 - xx2).|| ^2))
by NDIFF_8:1;
then
||.(p1 - p2).|| = ||.(xx1 - xx2).||
by SQUARE_1:22;
then
||.(p1 - p2).|| = |.(x1 - x2).|
by A23, EUCLID:def 2;
then A24:
||.((f /. p1) - (f /. p2)).|| < r
by A15, A18, A2, A21, A22;
(
(ProjPMap2 (g,t)) . x1 = g . (
x1,
t) &
(ProjPMap2 (g,t)) . x2 = g . (
x2,
t) )
by A21, A22, MESFUN12:def 4;
then
(
(ProjPMap2 (g,t)) . x1 = f /. p1 &
(ProjPMap2 (g,t)) . x2 = f /. p2 )
by A2, A21, A22, PARTFUN1:def 6;
then
((ProjPMap2 (g,t)) . x1) - ((ProjPMap2 (g,t)) . x2) = (f /. p1) - (f /. p2)
by DUALSP03:4;
hence
|.(((ProjPMap2 (g,t)) . x1) - ((ProjPMap2 (g,t)) . x2)).| < r
by A24, EUCLID:def 2;
verum end;
hence
ex
s being
Real st
(
0 < s & ( for
x1,
x2 being
Real st
x1 in dom (ProjPMap2 (g,t)) &
x2 in dom (ProjPMap2 (g,t)) &
|.(x1 - x2).| < s holds
|.(((ProjPMap2 (g,t)) . x1) - ((ProjPMap2 (g,t)) . x2)).| < r ) )
by A14;
verum
end;
hence
ProjPMap2 (g,t) is uniformly_continuous
by FCONT_2:def 1; verum