Metamath Proof Explorer


Theorem idcncf

Description: The identity function is a continuous function on CC . (Contributed by Jeff Madsen, 11-Jun-2010) (Moved into main set.mm as cncfmptid and may be deleted by mathbox owner, JM. --MC 12-Sep-2015.) (Revised by Mario Carneiro, 12-Sep-2015)

Ref Expression
Hypothesis idcncf.1
|- F = ( x e. CC |-> x )
Assertion idcncf
|- F e. ( CC -cn-> CC )

Proof

Step Hyp Ref Expression
1 idcncf.1
 |-  F = ( x e. CC |-> x )
2 ssid
 |-  CC C_ CC
3 cncfmptid
 |-  ( ( CC C_ CC /\ CC C_ CC ) -> ( x e. CC |-> x ) e. ( CC -cn-> CC ) )
4 2 2 3 mp2an
 |-  ( x e. CC |-> x ) e. ( CC -cn-> CC )
5 1 4 eqeltri
 |-  F e. ( CC -cn-> CC )