Metamath Proof Explorer


Theorem prdsless

Description: Closure of the order relation on a structure product. (Contributed by Mario Carneiro, 16-Aug-2015)

Ref Expression
Hypotheses prdsbas.p P=S𝑠R
prdsbas.s φSV
prdsbas.r φRW
prdsbas.b B=BaseP
prdsbas.i φdomR=I
prdsle.l ˙=P
Assertion prdsless φ˙B×B

Proof

Step Hyp Ref Expression
1 prdsbas.p P=S𝑠R
2 prdsbas.s φSV
3 prdsbas.r φRW
4 prdsbas.b B=BaseP
5 prdsbas.i φdomR=I
6 prdsle.l ˙=P
7 1 2 3 4 5 6 prdsle φ˙=fg|fgBxIfxRxgx
8 vex fV
9 vex gV
10 8 9 prss fBgBfgB
11 10 anbi1i fBgBxIfxRxgxfgBxIfxRxgx
12 11 opabbii fg|fBgBxIfxRxgx=fg|fgBxIfxRxgx
13 opabssxp fg|fBgBxIfxRxgxB×B
14 12 13 eqsstrri fg|fgBxIfxRxgxB×B
15 7 14 eqsstrdi φ˙B×B