let L be complete LATTICE; for N being net of L
for x being Element of L st N in NetUniv L holds
( [N,x] in lim_inf-Convergence L iff for M being subnet of N st M in NetUniv L holds
x = lim_inf M )
let N be net of L; for x being Element of L st N in NetUniv L holds
( [N,x] in lim_inf-Convergence L iff for M being subnet of N st M in NetUniv L holds
x = lim_inf M )
let x be Element of L; ( N in NetUniv L implies ( [N,x] in lim_inf-Convergence L iff for M being subnet of N st M in NetUniv L holds
x = lim_inf M ) )
assume A1:
N in NetUniv L
; ( [N,x] in lim_inf-Convergence L iff for M being subnet of N st M in NetUniv L holds
x = lim_inf M )
hence
( [N,x] in lim_inf-Convergence L implies for M being subnet of N st M in NetUniv L holds
x = lim_inf M )
by Def3; ( ( for M being subnet of N st M in NetUniv L holds
x = lim_inf M ) implies [N,x] in lim_inf-Convergence L )
assume A2:
for M being subnet of N st M in NetUniv L holds
x = lim_inf M
; [N,x] in lim_inf-Convergence L
then
for M being subnet of N st M in NetUniv L holds
x >= inf M
by A1, Th3;
then A3:
for p being greater_or_equal_to_id Function of N,N holds x >= inf (N * p)
by A1, Th10;
x = lim_inf N
by A1, A2, Th3;
then
for M being subnet of N holds x = lim_inf M
by A3, Th14;
hence
[N,x] in lim_inf-Convergence L
by A1, Def3; verum