Metamath Proof Explorer


Theorem fucoppclem

Description: Lemma for fucoppc . (Contributed by Zhi Wang, 18-Nov-2025)

Ref Expression
Hypotheses fucoppclem.o O = oppCat C
fucoppclem.p P = oppCat D
fucoppclem.n N = C Nat D
fucoppclem.f No typesetting found for |- ( ph -> F = ( oppFunc |` ( C Func D ) ) ) with typecode |-
fucoppclem.x φ X C Func D
fucoppclem.y φ Y C Func D
Assertion fucoppclem φ Y N X = F X O Nat P F Y

Proof

Step Hyp Ref Expression
1 fucoppclem.o O = oppCat C
2 fucoppclem.p P = oppCat D
3 fucoppclem.n N = C Nat D
4 fucoppclem.f Could not format ( ph -> F = ( oppFunc |` ( C Func D ) ) ) : No typesetting found for |- ( ph -> F = ( oppFunc |` ( C Func D ) ) ) with typecode |-
5 fucoppclem.x φ X C Func D
6 fucoppclem.y φ Y C Func D
7 eqid O Nat P = O Nat P
8 4 fveq1d Could not format ( ph -> ( F ` Y ) = ( ( oppFunc |` ( C Func D ) ) ` Y ) ) : No typesetting found for |- ( ph -> ( F ` Y ) = ( ( oppFunc |` ( C Func D ) ) ` Y ) ) with typecode |-
9 6 fvresd Could not format ( ph -> ( ( oppFunc |` ( C Func D ) ) ` Y ) = ( oppFunc ` Y ) ) : No typesetting found for |- ( ph -> ( ( oppFunc |` ( C Func D ) ) ` Y ) = ( oppFunc ` Y ) ) with typecode |-
10 8 9 eqtrd Could not format ( ph -> ( F ` Y ) = ( oppFunc ` Y ) ) : No typesetting found for |- ( ph -> ( F ` Y ) = ( oppFunc ` Y ) ) with typecode |-
11 4 fveq1d Could not format ( ph -> ( F ` X ) = ( ( oppFunc |` ( C Func D ) ) ` X ) ) : No typesetting found for |- ( ph -> ( F ` X ) = ( ( oppFunc |` ( C Func D ) ) ` X ) ) with typecode |-
12 5 fvresd Could not format ( ph -> ( ( oppFunc |` ( C Func D ) ) ` X ) = ( oppFunc ` X ) ) : No typesetting found for |- ( ph -> ( ( oppFunc |` ( C Func D ) ) ` X ) = ( oppFunc ` X ) ) with typecode |-
13 11 12 eqtrd Could not format ( ph -> ( F ` X ) = ( oppFunc ` X ) ) : No typesetting found for |- ( ph -> ( F ` X ) = ( oppFunc ` X ) ) with typecode |-
14 5 func1st2nd φ 1 st X C Func D 2 nd X
15 14 funcrcl2 φ C Cat
16 14 funcrcl3 φ D Cat
17 1 2 3 7 10 13 15 16 natoppfb φ Y N X = F X O Nat P F Y