theorem Th41:
for
x0 being
Real for
f,
f1,
f2 being
PartFunc of
REAL,
REAL st
f1 is_convergent_in x0 &
f2 is_convergent_in x0 &
lim (
f1,
x0)
= lim (
f2,
x0) & ( for
r1,
r2 being
Real st
r1 < x0 &
x0 < r2 holds
ex
g1,
g2 being
Real st
(
r1 < g1 &
g1 < x0 &
g1 in dom f &
g2 < r2 &
x0 < g2 &
g2 in dom f ) ) & ex
r being
Real st
(
0 < r & ( for
g being
Real st
g in (dom f) /\ (].(x0 - r),x0.[ \/ ].x0,(x0 + r).[) holds
(
f1 . g <= f . g &
f . g <= f2 . g ) ) & ( (
(dom f1) /\ (].(x0 - r),x0.[ \/ ].x0,(x0 + r).[) c= (dom f2) /\ (].(x0 - r),x0.[ \/ ].x0,(x0 + r).[) &
(dom f) /\ (].(x0 - r),x0.[ \/ ].x0,(x0 + r).[) c= (dom f1) /\ (].(x0 - r),x0.[ \/ ].x0,(x0 + r).[) ) or (
(dom f2) /\ (].(x0 - r),x0.[ \/ ].x0,(x0 + r).[) c= (dom f1) /\ (].(x0 - r),x0.[ \/ ].x0,(x0 + r).[) &
(dom f) /\ (].(x0 - r),x0.[ \/ ].x0,(x0 + r).[) c= (dom f2) /\ (].(x0 - r),x0.[ \/ ].x0,(x0 + r).[) ) ) ) holds
(
f is_convergent_in x0 &
lim (
f,
x0)
= lim (
f1,
x0) )