Metamath Proof Explorer


Theorem climre

Description: Limit of the real part of a sequence. Proposition 12-2.4(c) of Gleason p. 172. (Contributed by NM, 7-Jun-2006) (Revised by Mario Carneiro, 9-Feb-2014)

Ref Expression
Hypotheses climcn1lem.1
|- Z = ( ZZ>= ` M )
climcn1lem.2
|- ( ph -> F ~~> A )
climcn1lem.4
|- ( ph -> G e. W )
climcn1lem.5
|- ( ph -> M e. ZZ )
climcn1lem.6
|- ( ( ph /\ k e. Z ) -> ( F ` k ) e. CC )
climre.7
|- ( ( ph /\ k e. Z ) -> ( G ` k ) = ( Re ` ( F ` k ) ) )
Assertion climre
|- ( ph -> G ~~> ( Re ` A ) )

Proof

Step Hyp Ref Expression
1 climcn1lem.1
 |-  Z = ( ZZ>= ` M )
2 climcn1lem.2
 |-  ( ph -> F ~~> A )
3 climcn1lem.4
 |-  ( ph -> G e. W )
4 climcn1lem.5
 |-  ( ph -> M e. ZZ )
5 climcn1lem.6
 |-  ( ( ph /\ k e. Z ) -> ( F ` k ) e. CC )
6 climre.7
 |-  ( ( ph /\ k e. Z ) -> ( G ` k ) = ( Re ` ( F ` k ) ) )
7 ref
 |-  Re : CC --> RR
8 ax-resscn
 |-  RR C_ CC
9 fss
 |-  ( ( Re : CC --> RR /\ RR C_ CC ) -> Re : CC --> CC )
10 7 8 9 mp2an
 |-  Re : CC --> CC
11 recn2
 |-  ( ( A e. CC /\ x e. RR+ ) -> E. y e. RR+ A. z e. CC ( ( abs ` ( z - A ) ) < y -> ( abs ` ( ( Re ` z ) - ( Re ` A ) ) ) < x ) )
12 1 2 3 4 5 10 11 6 climcn1lem
 |-  ( ph -> G ~~> ( Re ` A ) )