let X be non empty set ; for Y, Z being non empty Subset of ExtREAL
for F1 being Function of X,Y
for F2 being Function of X,Z st F1 is bounded & F2 is bounded holds
F1 + F2 is bounded
let Y, Z be non empty Subset of ExtREAL; for F1 being Function of X,Y
for F2 being Function of X,Z st F1 is bounded & F2 is bounded holds
F1 + F2 is bounded
let F1 be Function of X,Y; for F2 being Function of X,Z st F1 is bounded & F2 is bounded holds
F1 + F2 is bounded
let F2 be Function of X,Z; ( F1 is bounded & F2 is bounded implies F1 + F2 is bounded )
assume that
A1:
F1 is bounded
and
A2:
F2 is bounded
; F1 + F2 is bounded
A3:
F1 + F2 is bounded_below
by A1, A2, Th50;
F1 + F2 is bounded_above
by A1, A2, Th49;
hence
F1 + F2 is bounded
by A3; verum