Metamath Proof Explorer


Theorem climreu

Description: An infinite sequence of complex numbers converges to at most one limit. (Contributed by NM, 25-Dec-2005)

Ref Expression
Assertion climreu
|- ( F ~~> A -> E! x e. CC F ~~> x )

Proof

Step Hyp Ref Expression
1 climeu
 |-  ( F ~~> A -> E! x F ~~> x )
2 climcl
 |-  ( F ~~> x -> x e. CC )
3 2 pm4.71ri
 |-  ( F ~~> x <-> ( x e. CC /\ F ~~> x ) )
4 3 eubii
 |-  ( E! x F ~~> x <-> E! x ( x e. CC /\ F ~~> x ) )
5 df-reu
 |-  ( E! x e. CC F ~~> x <-> E! x ( x e. CC /\ F ~~> x ) )
6 4 5 bitr4i
 |-  ( E! x F ~~> x <-> E! x e. CC F ~~> x )
7 1 6 sylib
 |-  ( F ~~> A -> E! x e. CC F ~~> x )