theorem Th63:
for
x0 being
Real for
f,
f1,
f2 being
PartFunc of
REAL,
REAL st
f1 is_left_convergent_in x0 &
f2 is_left_convergent_in x0 &
lim_left (
f1,
x0)
= lim_left (
f2,
x0) & ( for
r being
Real st
r < x0 holds
ex
g being
Real st
(
r < g &
g < x0 &
g in dom f ) ) & ex
r being
Real st
(
0 < r & ( for
g being
Real st
g in (dom f) /\ ].(x0 - r),x0.[ holds
(
f1 . g <= f . g &
f . g <= f2 . g ) ) & ( (
(dom f1) /\ ].(x0 - r),x0.[ c= (dom f2) /\ ].(x0 - r),x0.[ &
(dom f) /\ ].(x0 - r),x0.[ c= (dom f1) /\ ].(x0 - r),x0.[ ) or (
(dom f2) /\ ].(x0 - r),x0.[ c= (dom f1) /\ ].(x0 - r),x0.[ &
(dom f) /\ ].(x0 - r),x0.[ c= (dom f2) /\ ].(x0 - r),x0.[ ) ) ) holds
(
f is_left_convergent_in x0 &
lim_left (
f,
x0)
= lim_left (
f1,
x0) )