let E be RealNormSpace; :: thesis: for F being RealBanachSpace
for A being non empty Subset of E
for B being non empty Subset of F
for Fai being PartFunc of [:E,F:],F st B is closed & [:A,B:] c= dom Fai & ( for x being Point of E
for y being Point of F st x in A & y in B holds
Fai . (x,y) in B ) & ( for y being Point of F st y in B holds
for x0 being Point of E st x0 in A holds
for e being Real st 0 < e holds
ex d being Real st
( 0 < d & ( for x1 being Point of E st x1 in A & ||.(x1 - x0).|| < d holds
||.((Fai /. [x1,y]) - (Fai /. [x0,y])).|| < e ) ) ) & ex k being Real st
( 0 < k & k < 1 & ( for x being Point of E st x in A holds
for y1, y2 being Point of F st y1 in B & y2 in B holds
||.((Fai /. [x,y1]) - (Fai /. [x,y2])).|| <= k * ||.(y1 - y2).|| ) ) holds
( ex g being PartFunc of E,F st
( g is_continuous_on A & dom g = A & rng g c= B & ( for x being Point of E st x in A holds
Fai . (x,(g . x)) = g . x ) ) & ( for g1, g2 being PartFunc of E,F st dom g1 = A & rng g1 c= B & dom g2 = A & rng g2 c= B & ( for x being Point of E st x in A holds
Fai . (x,(g1 . x)) = g1 . x ) & ( for x being Point of E st x in A holds
Fai . (x,(g2 . x)) = g2 . x ) holds
g1 = g2 ) )

let F be RealBanachSpace; :: thesis: for A being non empty Subset of E
for B being non empty Subset of F
for Fai being PartFunc of [:E,F:],F st B is closed & [:A,B:] c= dom Fai & ( for x being Point of E
for y being Point of F st x in A & y in B holds
Fai . (x,y) in B ) & ( for y being Point of F st y in B holds
for x0 being Point of E st x0 in A holds
for e being Real st 0 < e holds
ex d being Real st
( 0 < d & ( for x1 being Point of E st x1 in A & ||.(x1 - x0).|| < d holds
||.((Fai /. [x1,y]) - (Fai /. [x0,y])).|| < e ) ) ) & ex k being Real st
( 0 < k & k < 1 & ( for x being Point of E st x in A holds
for y1, y2 being Point of F st y1 in B & y2 in B holds
||.((Fai /. [x,y1]) - (Fai /. [x,y2])).|| <= k * ||.(y1 - y2).|| ) ) holds
( ex g being PartFunc of E,F st
( g is_continuous_on A & dom g = A & rng g c= B & ( for x being Point of E st x in A holds
Fai . (x,(g . x)) = g . x ) ) & ( for g1, g2 being PartFunc of E,F st dom g1 = A & rng g1 c= B & dom g2 = A & rng g2 c= B & ( for x being Point of E st x in A holds
Fai . (x,(g1 . x)) = g1 . x ) & ( for x being Point of E st x in A holds
Fai . (x,(g2 . x)) = g2 . x ) holds
g1 = g2 ) )

let A be non empty Subset of E; :: thesis: for B being non empty Subset of F
for Fai being PartFunc of [:E,F:],F st B is closed & [:A,B:] c= dom Fai & ( for x being Point of E
for y being Point of F st x in A & y in B holds
Fai . (x,y) in B ) & ( for y being Point of F st y in B holds
for x0 being Point of E st x0 in A holds
for e being Real st 0 < e holds
ex d being Real st
( 0 < d & ( for x1 being Point of E st x1 in A & ||.(x1 - x0).|| < d holds
||.((Fai /. [x1,y]) - (Fai /. [x0,y])).|| < e ) ) ) & ex k being Real st
( 0 < k & k < 1 & ( for x being Point of E st x in A holds
for y1, y2 being Point of F st y1 in B & y2 in B holds
||.((Fai /. [x,y1]) - (Fai /. [x,y2])).|| <= k * ||.(y1 - y2).|| ) ) holds
( ex g being PartFunc of E,F st
( g is_continuous_on A & dom g = A & rng g c= B & ( for x being Point of E st x in A holds
Fai . (x,(g . x)) = g . x ) ) & ( for g1, g2 being PartFunc of E,F st dom g1 = A & rng g1 c= B & dom g2 = A & rng g2 c= B & ( for x being Point of E st x in A holds
Fai . (x,(g1 . x)) = g1 . x ) & ( for x being Point of E st x in A holds
Fai . (x,(g2 . x)) = g2 . x ) holds
g1 = g2 ) )

let B be non empty Subset of F; :: thesis: for Fai being PartFunc of [:E,F:],F st B is closed & [:A,B:] c= dom Fai & ( for x being Point of E
for y being Point of F st x in A & y in B holds
Fai . (x,y) in B ) & ( for y being Point of F st y in B holds
for x0 being Point of E st x0 in A holds
for e being Real st 0 < e holds
ex d being Real st
( 0 < d & ( for x1 being Point of E st x1 in A & ||.(x1 - x0).|| < d holds
||.((Fai /. [x1,y]) - (Fai /. [x0,y])).|| < e ) ) ) & ex k being Real st
( 0 < k & k < 1 & ( for x being Point of E st x in A holds
for y1, y2 being Point of F st y1 in B & y2 in B holds
||.((Fai /. [x,y1]) - (Fai /. [x,y2])).|| <= k * ||.(y1 - y2).|| ) ) holds
( ex g being PartFunc of E,F st
( g is_continuous_on A & dom g = A & rng g c= B & ( for x being Point of E st x in A holds
Fai . (x,(g . x)) = g . x ) ) & ( for g1, g2 being PartFunc of E,F st dom g1 = A & rng g1 c= B & dom g2 = A & rng g2 c= B & ( for x being Point of E st x in A holds
Fai . (x,(g1 . x)) = g1 . x ) & ( for x being Point of E st x in A holds
Fai . (x,(g2 . x)) = g2 . x ) holds
g1 = g2 ) )

let Fai be PartFunc of [:E,F:],F; :: thesis: ( B is closed & [:A,B:] c= dom Fai & ( for x being Point of E
for y being Point of F st x in A & y in B holds
Fai . (x,y) in B ) & ( for y being Point of F st y in B holds
for x0 being Point of E st x0 in A holds
for e being Real st 0 < e holds
ex d being Real st
( 0 < d & ( for x1 being Point of E st x1 in A & ||.(x1 - x0).|| < d holds
||.((Fai /. [x1,y]) - (Fai /. [x0,y])).|| < e ) ) ) & ex k being Real st
( 0 < k & k < 1 & ( for x being Point of E st x in A holds
for y1, y2 being Point of F st y1 in B & y2 in B holds
||.((Fai /. [x,y1]) - (Fai /. [x,y2])).|| <= k * ||.(y1 - y2).|| ) ) implies ( ex g being PartFunc of E,F st
( g is_continuous_on A & dom g = A & rng g c= B & ( for x being Point of E st x in A holds
Fai . (x,(g . x)) = g . x ) ) & ( for g1, g2 being PartFunc of E,F st dom g1 = A & rng g1 c= B & dom g2 = A & rng g2 c= B & ( for x being Point of E st x in A holds
Fai . (x,(g1 . x)) = g1 . x ) & ( for x being Point of E st x in A holds
Fai . (x,(g2 . x)) = g2 . x ) holds
g1 = g2 ) ) )

assume that
A1: B is closed and
A2: [:A,B:] c= dom Fai and
A3: for x being Point of E
for y being Point of F st x in A & y in B holds
Fai . (x,y) in B and
A4: for y being Point of F st y in B holds
for x0 being Point of E st x0 in A holds
for e being Real st 0 < e holds
ex d being Real st
( 0 < d & ( for x1 being Point of E st x1 in A & ||.(x1 - x0).|| < d holds
||.((Fai /. [x1,y]) - (Fai /. [x0,y])).|| < e ) ) and
A5: ex k being Real st
( 0 < k & k < 1 & ( for x being Point of E st x in A holds
for y1, y2 being Point of F st y1 in B & y2 in B holds
||.((Fai /. [x,y1]) - (Fai /. [x,y2])).|| <= k * ||.(y1 - y2).|| ) ) ; :: thesis: ( ex g being PartFunc of E,F st
( g is_continuous_on A & dom g = A & rng g c= B & ( for x being Point of E st x in A holds
Fai . (x,(g . x)) = g . x ) ) & ( for g1, g2 being PartFunc of E,F st dom g1 = A & rng g1 c= B & dom g2 = A & rng g2 c= B & ( for x being Point of E st x in A holds
Fai . (x,(g1 . x)) = g1 . x ) & ( for x being Point of E st x in A holds
Fai . (x,(g2 . x)) = g2 . x ) holds
g1 = g2 ) )

thus ex g being PartFunc of E,F st
( g is_continuous_on A & dom g = A & rng g c= B & ( for x being Point of E st x in A holds
Fai . (x,(g . x)) = g . x ) ) :: thesis: for g1, g2 being PartFunc of E,F st dom g1 = A & rng g1 c= B & dom g2 = A & rng g2 c= B & ( for x being Point of E st x in A holds
Fai . (x,(g1 . x)) = g1 . x ) & ( for x being Point of E st x in A holds
Fai . (x,(g2 . x)) = g2 . x ) holds
g1 = g2
proof
defpred S1[ object , object ] means ( $2 in B & Fai . ($1,$2) = $2 );
A6: for x, y1, y2 being object st x in A & S1[x,y1] & S1[x,y2] holds
y1 = y2 by A1, A2, A3, A4, A5, FIXPOINT2;
A7: for x being object st x in A holds
ex y being object st S1[x,y]
proof
let x be object ; :: thesis: ( x in A implies ex y being object st S1[x,y] )
assume A8: x in A ; :: thesis: ex y being object st S1[x,y]
then reconsider x0 = x as Point of E ;
consider y being Point of F such that
A9: ( y in B & Fai . (x0,y) = y ) by A1, A2, A3, A4, A5, A8, FIXPOINT2;
take y ; :: thesis: S1[x,y]
thus S1[x,y] by A9; :: thesis: verum
end;
consider g being Function such that
A10: ( dom g = A & ( for x being object st x in A holds
S1[x,g . x] ) ) from FUNCT_1:sch 2(A6, A7);
A11: rng g c= B
proof
let y be object ; :: according to TARSKI:def 3 :: thesis: ( not y in rng g or y in B )
assume y in rng g ; :: thesis: y in B
then consider x being object such that
A12: ( x in dom g & y = g . x ) by FUNCT_1:def 3;
thus y in B by A10, A12; :: thesis: verum
end;
then rng g c= the carrier of F by XBOOLE_1:1;
then g in PFuncs ( the carrier of E, the carrier of F) by A10, PARTFUN1:def 3;
then reconsider g = g as PartFunc of E,F by PARTFUN1:46;
take g ; :: thesis: ( g is_continuous_on A & dom g = A & rng g c= B & ( for x being Point of E st x in A holds
Fai . (x,(g . x)) = g . x ) )

for z0 being Point of E
for r being Real st z0 in A & 0 < r holds
ex s being Real st
( 0 < s & ( for z1 being Point of E st z1 in A & ||.(z1 - z0).|| < s holds
||.((g /. z1) - (g /. z0)).|| < r ) )
proof
let z0 be Point of E; :: thesis: for r being Real st z0 in A & 0 < r holds
ex s being Real st
( 0 < s & ( for z1 being Point of E st z1 in A & ||.(z1 - z0).|| < s holds
||.((g /. z1) - (g /. z0)).|| < r ) )

let r be Real; :: thesis: ( z0 in A & 0 < r implies ex s being Real st
( 0 < s & ( for z1 being Point of E st z1 in A & ||.(z1 - z0).|| < s holds
||.((g /. z1) - (g /. z0)).|| < r ) ) )

assume A15: ( z0 in A & 0 < r ) ; :: thesis: ex s being Real st
( 0 < s & ( for z1 being Point of E st z1 in A & ||.(z1 - z0).|| < s holds
||.((g /. z1) - (g /. z0)).|| < r ) )

then A16: Fai . (z0,(g . z0)) = g . z0 by A10;
A17: g . z0 in rng g by A10, A15, FUNCT_1:3;
g . z0 = g /. z0 by A10, A15, PARTFUN1:def 6;
then consider s being Real such that
A18: ( 0 < s & ( for x1 being Point of E
for y1 being Point of F st x1 in A & y1 in B & Fai . (x1,y1) = y1 & ||.(x1 - z0).|| < s holds
||.(y1 - (g /. z0)).|| < r ) ) by A1, A2, A3, A4, A5, A11, A15, A16, A17, FIXPOINT2;
take s ; :: thesis: ( 0 < s & ( for z1 being Point of E st z1 in A & ||.(z1 - z0).|| < s holds
||.((g /. z1) - (g /. z0)).|| < r ) )

thus 0 < s by A18; :: thesis: for z1 being Point of E st z1 in A & ||.(z1 - z0).|| < s holds
||.((g /. z1) - (g /. z0)).|| < r

let z1 be Point of E; :: thesis: ( z1 in A & ||.(z1 - z0).|| < s implies ||.((g /. z1) - (g /. z0)).|| < r )
assume A19: ( z1 in A & ||.(z1 - z0).|| < s ) ; :: thesis: ||.((g /. z1) - (g /. z0)).|| < r
then A20: Fai . (z1,(g . z1)) = g . z1 by A10;
A21: g . z1 in B by A10, A19;
g . z1 = g /. z1 by A10, A19, PARTFUN1:def 6;
hence ||.((g /. z1) - (g /. z0)).|| < r by A18, A19, A20, A21; :: thesis: verum
end;
hence g is_continuous_on A by A10, NFCONT_1:19; :: thesis: ( dom g = A & rng g c= B & ( for x being Point of E st x in A holds
Fai . (x,(g . x)) = g . x ) )

thus ( dom g = A & rng g c= B ) by A10, A11; :: thesis: for x being Point of E st x in A holds
Fai . (x,(g . x)) = g . x

thus for x being Point of E st x in A holds
Fai . (x,(g . x)) = g . x by A10; :: thesis: verum
end;
let g1, g2 be PartFunc of E,F; :: thesis: ( dom g1 = A & rng g1 c= B & dom g2 = A & rng g2 c= B & ( for x being Point of E st x in A holds
Fai . (x,(g1 . x)) = g1 . x ) & ( for x being Point of E st x in A holds
Fai . (x,(g2 . x)) = g2 . x ) implies g1 = g2 )

assume A22: ( dom g1 = A & rng g1 c= B & dom g2 = A & rng g2 c= B & ( for x being Point of E st x in A holds
Fai . (x,(g1 . x)) = g1 . x ) & ( for x being Point of E st x in A holds
Fai . (x,(g2 . x)) = g2 . x ) ) ; :: thesis: g1 = g2
for x being object st x in dom g1 holds
g1 . x = g2 . x
proof
let x be object ; :: thesis: ( x in dom g1 implies g1 . x = g2 . x )
assume A23: x in dom g1 ; :: thesis: g1 . x = g2 . x
then reconsider y = x as Point of E ;
A24: g1 . y in rng g1 by A23, FUNCT_1:3;
then reconsider z1 = g1 . y as Point of F ;
A25: g2 . y in rng g2 by A22, A23, FUNCT_1:3;
then reconsider z2 = g2 . y as Point of F ;
( Fai . (y,z1) = z1 & Fai . (y,z2) = z2 & z1 in B & z2 in B & y in A ) by A22, A23, A24, A25;
hence g1 . x = g2 . x by A1, A2, A3, A4, A5, FIXPOINT2; :: thesis: verum
end;
hence g1 = g2 by A22, FUNCT_1:2; :: thesis: verum