let X be non empty TopSpace; for n being Nat
for p1, p2 being Point of (TOP-REAL n)
for f1, f2 being Function of X,R^1 st f1 is continuous & f2 is continuous holds
ex g being Function of X,(TOP-REAL n) st
( ( for r being Point of X holds g . r = ((f1 . r) * p1) + ((f2 . r) * p2) ) & g is continuous )
let n be Nat; for p1, p2 being Point of (TOP-REAL n)
for f1, f2 being Function of X,R^1 st f1 is continuous & f2 is continuous holds
ex g being Function of X,(TOP-REAL n) st
( ( for r being Point of X holds g . r = ((f1 . r) * p1) + ((f2 . r) * p2) ) & g is continuous )
let p1, p2 be Point of (TOP-REAL n); for f1, f2 being Function of X,R^1 st f1 is continuous & f2 is continuous holds
ex g being Function of X,(TOP-REAL n) st
( ( for r being Point of X holds g . r = ((f1 . r) * p1) + ((f2 . r) * p2) ) & g is continuous )
let f1, f2 be Function of X,R^1; ( f1 is continuous & f2 is continuous implies ex g being Function of X,(TOP-REAL n) st
( ( for r being Point of X holds g . r = ((f1 . r) * p1) + ((f2 . r) * p2) ) & g is continuous ) )
assume that
A1:
f1 is continuous
and
A2:
f2 is continuous
; ex g being Function of X,(TOP-REAL n) st
( ( for r being Point of X holds g . r = ((f1 . r) * p1) + ((f2 . r) * p2) ) & g is continuous )
consider g1 being Function of X,(TOP-REAL n) such that
A3:
for r being Point of X holds g1 . r = (f1 . r) * p1
and
A4:
g1 is continuous
by A1, Th9;
consider g2 being Function of X,(TOP-REAL n) such that
A5:
for r being Point of X holds g2 . r = (f2 . r) * p2
and
A6:
g2 is continuous
by A2, Th9;
consider g being Function of X,(TOP-REAL n) such that
A7:
for r being Point of X holds g . r = (g1 . r) + (g2 . r)
and
A8:
g is continuous
by A4, A6, Th12;
for r being Point of X holds g . r = ((f1 . r) * p1) + ((f2 . r) * p2)
proof
let r be
Point of
X;
g . r = ((f1 . r) * p1) + ((f2 . r) * p2)
g . r = (g1 . r) + (g2 . r)
by A7;
then
g . r = (g1 . r) + ((f2 . r) * p2)
by A5;
hence
g . r = ((f1 . r) * p1) + ((f2 . r) * p2)
by A3;
verum
end;
hence
ex g being Function of X,(TOP-REAL n) st
( ( for r being Point of X holds g . r = ((f1 . r) * p1) + ((f2 . r) * p2) ) & g is continuous )
by A8; verum