Metamath Proof Explorer


Theorem colleq12d

Description: Equality theorem for the collection operation. (Contributed by Rohan Ridenour, 11-Aug-2023)

Ref Expression
Hypotheses colleq12d.1 φF=G
colleq12d.2 φA=B
Assertion colleq12d φFCollA=GCollB

Proof

Step Hyp Ref Expression
1 colleq12d.1 φF=G
2 colleq12d.2 φA=B
3 1 imaeq1d φFx=Gx
4 3 scotteqd φScottFx=ScottGx
5 2 4 iuneq12d φxAScottFx=xBScottGx
6 df-coll FCollA=xAScottFx
7 df-coll GCollB=xBScottGx
8 5 6 7 3eqtr4g φFCollA=GCollB