Metamath Proof Explorer


Theorem cnvref4

Description: Two ways to say that a relation is a subclass. (Contributed by Peter Mazsa, 11-Apr-2023)

Ref Expression
Assertion cnvref4 Rel R R dom R × ran R S dom R × ran R R S

Proof

Step Hyp Ref Expression
1 dfrel6 Rel R R dom R × ran R = R
2 1 biimpi Rel R R dom R × ran R = R
3 2 dmeqd Rel R dom R dom R × ran R = dom R
4 2 rneqd Rel R ran R dom R × ran R = ran R
5 3 4 xpeq12d Rel R dom R dom R × ran R × ran R dom R × ran R = dom R × ran R
6 5 ineq2d Rel R S dom R dom R × ran R × ran R dom R × ran R = S dom R × ran R
7 6 sseq2d Rel R R dom R × ran R S dom R dom R × ran R × ran R dom R × ran R R dom R × ran R S dom R × ran R
8 relxp Rel dom R × ran R
9 relin2 Rel dom R × ran R Rel R dom R × ran R
10 relssinxpdmrn Rel R dom R × ran R R dom R × ran R S dom R dom R × ran R × ran R dom R × ran R R dom R × ran R S
11 8 9 10 mp2b R dom R × ran R S dom R dom R × ran R × ran R dom R × ran R R dom R × ran R S
12 2 sseq1d Rel R R dom R × ran R S R S
13 11 12 bitrid Rel R R dom R × ran R S dom R dom R × ran R × ran R dom R × ran R R S
14 7 13 bitr3d Rel R R dom R × ran R S dom R × ran R R S