Metamath Proof Explorer


Theorem qtopconn

Description: A quotient of a connected space is connected. (Contributed by Mario Carneiro, 24-Mar-2015)

Ref Expression
Hypothesis qtopcmp.1 ⊢ X = ⋃ J
Assertion qtopconn ⊢ J ∈ Conn ∧ F Fn X → J qTop F ∈ Conn

Proof

Step Hyp Ref Expression
1 qtopcmp.1 ⊢ X = ⋃ J
2 conntop ⊢ J ∈ Conn → J ∈ Top
3 eqid ⊢ ⋃ J qTop F = ⋃ J qTop F
4 3 cnconn ⊢ J ∈ Conn ∧ F : X ⟶ onto ⋃ J qTop F ∧ F ∈ J Cn J qTop F → J qTop F ∈ Conn
5 1 2 4 qtopcmplem ⊢ J ∈ Conn ∧ F Fn X → J qTop F ∈ Conn