Metamath Proof Explorer


Theorem ssrelrel

Description: A subclass relationship determined by ordered triples. Use relrelss to express the antecedent in terms of the relation predicate. (Contributed by NM, 17-Dec-2008) (Proof shortened by Andrew Salmon, 27-Aug-2011)

Ref Expression
Assertion ssrelrel AV×V×VABxyzxyzAxyzB

Proof

Step Hyp Ref Expression
1 ssel ABxyzAxyzB
2 1 alrimiv ABzxyzAxyzB
3 2 alrimivv ABxyzxyzAxyzB
4 elvvv wV×V×Vxyzw=xyz
5 eleq1 w=xyzwAxyzA
6 eleq1 w=xyzwBxyzB
7 5 6 imbi12d w=xyzwAwBxyzAxyzB
8 7 biimprcd xyzAxyzBw=xyzwAwB
9 8 alimi zxyzAxyzBzw=xyzwAwB
10 19.23v zw=xyzwAwBzw=xyzwAwB
11 9 10 sylib zxyzAxyzBzw=xyzwAwB
12 11 2alimi xyzxyzAxyzBxyzw=xyzwAwB
13 19.23vv xyzw=xyzwAwBxyzw=xyzwAwB
14 12 13 sylib xyzxyzAxyzBxyzw=xyzwAwB
15 4 14 biimtrid xyzxyzAxyzBwV×V×VwAwB
16 15 com23 xyzxyzAxyzBwAwV×V×VwB
17 16 a2d xyzxyzAxyzBwAwV×V×VwAwB
18 17 alimdv xyzxyzAxyzBwwAwV×V×VwwAwB
19 dfss2 AV×V×VwwAwV×V×V
20 dfss2 ABwwAwB
21 18 19 20 3imtr4g xyzxyzAxyzBAV×V×VAB
22 21 com12 AV×V×VxyzxyzAxyzBAB
23 3 22 impbid2 AV×V×VABxyzxyzAxyzB