Metamath Proof Explorer


Theorem cvrfval

Description: Value of covers relation "is covered by". (Contributed by NM, 18-Sep-2011)

Ref Expression
Hypotheses cvrfval.b B=BaseK
cvrfval.s <˙=<K
cvrfval.c C=K
Assertion cvrfval KAC=xy|xByBx<˙y¬zBx<˙zz<˙y

Proof

Step Hyp Ref Expression
1 cvrfval.b B=BaseK
2 cvrfval.s <˙=<K
3 cvrfval.c C=K
4 elex KAKV
5 fveq2 p=KBasep=BaseK
6 5 1 eqtr4di p=KBasep=B
7 6 eleq2d p=KxBasepxB
8 6 eleq2d p=KyBasepyB
9 7 8 anbi12d p=KxBasepyBasepxByB
10 fveq2 p=K<p=<K
11 10 2 eqtr4di p=K<p=<˙
12 11 breqd p=Kx<pyx<˙y
13 11 breqd p=Kx<pzx<˙z
14 11 breqd p=Kz<pyz<˙y
15 13 14 anbi12d p=Kx<pzz<pyx<˙zz<˙y
16 6 15 rexeqbidv p=KzBasepx<pzz<pyzBx<˙zz<˙y
17 16 notbid p=K¬zBasepx<pzz<py¬zBx<˙zz<˙y
18 9 12 17 3anbi123d p=KxBasepyBasepx<py¬zBasepx<pzz<pyxByBx<˙y¬zBx<˙zz<˙y
19 18 opabbidv p=Kxy|xBasepyBasepx<py¬zBasepx<pzz<py=xy|xByBx<˙y¬zBx<˙zz<˙y
20 df-covers =pVxy|xBasepyBasepx<py¬zBasepx<pzz<py
21 3anass xByBx<˙y¬zBx<˙zz<˙yxByBx<˙y¬zBx<˙zz<˙y
22 21 opabbii xy|xByBx<˙y¬zBx<˙zz<˙y=xy|xByBx<˙y¬zBx<˙zz<˙y
23 1 fvexi BV
24 23 23 xpex B×BV
25 opabssxp xy|xByBx<˙y¬zBx<˙zz<˙yB×B
26 24 25 ssexi xy|xByBx<˙y¬zBx<˙zz<˙yV
27 22 26 eqeltri xy|xByBx<˙y¬zBx<˙zz<˙yV
28 19 20 27 fvmpt KVK=xy|xByBx<˙y¬zBx<˙zz<˙y
29 3 28 eqtrid KVC=xy|xByBx<˙y¬zBx<˙zz<˙y
30 4 29 syl KAC=xy|xByBx<˙y¬zBx<˙zz<˙y