let n be non zero Nat; for f being PartFunc of [:(CarProduct ((Seg n) --> RNS_Real)),RNS_Real:],RNS_Real
for g being PartFunc of [:(CarProduct ((Seg n) --> REAL)),REAL:],REAL
for P2 being PartFunc of (CarProduct ((Seg n) --> RNS_Real)),RNS_Real
for q being Element of REAL st f is_continuous_on dom f & f = g & P2 = ProjPMap2 (|.g.|,q) holds
P2 is_continuous_on dom P2
let f be PartFunc of [:(CarProduct ((Seg n) --> RNS_Real)),RNS_Real:],RNS_Real; for g being PartFunc of [:(CarProduct ((Seg n) --> REAL)),REAL:],REAL
for P2 being PartFunc of (CarProduct ((Seg n) --> RNS_Real)),RNS_Real
for q being Element of REAL st f is_continuous_on dom f & f = g & P2 = ProjPMap2 (|.g.|,q) holds
P2 is_continuous_on dom P2
let g be PartFunc of [:(CarProduct ((Seg n) --> REAL)),REAL:],REAL; for P2 being PartFunc of (CarProduct ((Seg n) --> RNS_Real)),RNS_Real
for q being Element of REAL st f is_continuous_on dom f & f = g & P2 = ProjPMap2 (|.g.|,q) holds
P2 is_continuous_on dom P2
let P2 be PartFunc of (CarProduct ((Seg n) --> RNS_Real)),RNS_Real; for q being Element of REAL st f is_continuous_on dom f & f = g & P2 = ProjPMap2 (|.g.|,q) holds
P2 is_continuous_on dom P2
let q be Element of REAL ; ( f is_continuous_on dom f & f = g & P2 = ProjPMap2 (|.g.|,q) implies P2 is_continuous_on dom P2 )
assume that
A1:
f is_continuous_on dom f
and
A2:
f = g
and
A3:
P2 = ProjPMap2 (|.g.|,q)
; P2 is_continuous_on dom P2
reconsider P1 = ProjPMap2 (g,q) as PartFunc of (CarProduct ((Seg n) --> RNS_Real)),RNS_Real by MEASUR15:42;
A4:
P1 is_continuous_on dom P1
by A1, A2, Th16;
dom P1 = dom |.(ProjPMap2 (g,q)).|
by VALUED_1:def 11;
then A5:
dom P1 = dom P2
by A3, MESFUN16:32;
for x0 being Point of (CarProduct ((Seg n) --> RNS_Real)) st x0 in dom P2 holds
P2 is_continuous_in x0
proof
let x0 be
Point of
(CarProduct ((Seg n) --> RNS_Real));
( x0 in dom P2 implies P2 is_continuous_in x0 )
assume A6:
x0 in dom P2
;
P2 is_continuous_in x0
reconsider yy =
q as
Point of
RNS_Real ;
reconsider p0 =
[x0,yy] as
Point of
[:(CarProduct ((Seg n) --> RNS_Real)),RNS_Real:] ;
A7:
P1 is_continuous_in x0
by A4, A5, A6;
for
r being
Real st
0 < r holds
ex
s being
Real st
(
0 < s & ( for
x1 being
Point of
(CarProduct ((Seg n) --> RNS_Real)) st
x1 in dom P2 &
||.(x1 - x0).|| < s holds
||.((P2 /. x1) - (P2 /. x0)).|| < r ) )
proof
let r be
Real;
( 0 < r implies ex s being Real st
( 0 < s & ( for x1 being Point of (CarProduct ((Seg n) --> RNS_Real)) st x1 in dom P2 & ||.(x1 - x0).|| < s holds
||.((P2 /. x1) - (P2 /. x0)).|| < r ) ) )
assume
0 < r
;
ex s being Real st
( 0 < s & ( for x1 being Point of (CarProduct ((Seg n) --> RNS_Real)) st x1 in dom P2 & ||.(x1 - x0).|| < s holds
||.((P2 /. x1) - (P2 /. x0)).|| < r ) )
then consider s0 being
Real such that A8:
0 < s0
and A9:
for
x1 being
Point of
(CarProduct ((Seg n) --> RNS_Real)) st
x1 in dom P1 &
||.(x1 - x0).|| < s0 holds
||.((P1 /. x1) - (P1 /. x0)).|| < r
by A7, NFCONT_1:7;
now for x1 being Point of (CarProduct ((Seg n) --> RNS_Real)) st x1 in dom P2 & ||.(x1 - x0).|| < s0 holds
||.((P2 /. x1) - (P2 /. x0)).|| < rlet x1 be
Point of
(CarProduct ((Seg n) --> RNS_Real));
( x1 in dom P2 & ||.(x1 - x0).|| < s0 implies ||.((P2 /. x1) - (P2 /. x0)).|| < r )assume that A10:
x1 in dom P2
and A11:
||.(x1 - x0).|| < s0
;
||.((P2 /. x1) - (P2 /. x0)).|| < rA12:
||.((P1 /. x1) - (P1 /. x0)).|| < r
by A5, A9, A10, A11;
reconsider xx1 =
x1,
xx0 =
x0 as
Element of
CarProduct ((Seg n) --> REAL) by MEASUR15:42;
A13:
xx1 in dom |.(ProjPMap2 (g,q)).|
by A10, A3, MESFUN16:32;
A14:
xx0 in dom |.(ProjPMap2 (g,q)).|
by A6, A3, MESFUN16:32;
A15:
P1 /. x1 = (ProjPMap2 (g,q)) . xx1
by A5, A10, PARTFUN1:def 6;
(ProjPMap2 (|.g.|,q)) . xx1 = |.(ProjPMap2 (g,q)).| . xx1
by MESFUN16:32;
then
P2 /. x1 = |.(ProjPMap2 (g,q)).| . xx1
by A3, A10, PARTFUN1:def 6;
then
P2 /. x1 = |.((ProjPMap2 (g,q)) . xx1).|
by A13, VALUED_1:def 11;
then A16:
P2 /. x1 = ||.(P1 /. x1).||
by A15, EUCLID:def 2;
A17:
P1 /. x0 = (ProjPMap2 (g,q)) . xx0
by A5, A6, PARTFUN1:def 6;
(ProjPMap2 (|.g.|,q)) . xx0 = |.(ProjPMap2 (g,q)).| . xx0
by MESFUN16:32;
then
P2 /. x0 = |.(ProjPMap2 (g,q)).| . xx0
by A3, A6, PARTFUN1:def 6;
then
P2 /. x0 = |.((ProjPMap2 (g,q)) . xx0).|
by A14, VALUED_1:def 11;
then
P2 /. x0 = ||.(P1 /. x0).||
by A17, EUCLID:def 2;
then
(P2 /. x1) - (P2 /. x0) = ||.(P1 /. x1).|| - ||.(P1 /. x0).||
by A16, DUALSP03:4;
then
||.((P2 /. x1) - (P2 /. x0)).|| = |.(||.(P1 /. x1).|| - ||.(P1 /. x0).||).|
by EUCLID:def 2;
then
||.((P2 /. x1) - (P2 /. x0)).|| <= ||.((P1 /. x1) - (P1 /. x0)).||
by NORMSP_1:9;
hence
||.((P2 /. x1) - (P2 /. x0)).|| < r
by A12, XXREAL_0:2;
verum end;
hence
ex
s being
Real st
(
0 < s & ( for
x1 being
Point of
(CarProduct ((Seg n) --> RNS_Real)) st
x1 in dom P2 &
||.(x1 - x0).|| < s holds
||.((P2 /. x1) - (P2 /. x0)).|| < r ) )
by A8;
verum
end;
hence
P2 is_continuous_in x0
by A6, NFCONT_1:7;
verum
end;
hence
P2 is_continuous_on dom P2
; verum