Metamath Proof Explorer


Theorem rtrclexlem

Description: Existence of relation implies existence of union with Cartesian product of domain and range. (Contributed by RP, 1-Nov-2020)

Ref Expression
Assertion rtrclexlem R V R dom R ran R × dom R ran R V

Proof

Step Hyp Ref Expression
1 dmexg R V dom R V
2 rnexg R V ran R V
3 1 2 unexd R V dom R ran R V
4 sqxpexg dom R ran R V dom R ran R × dom R ran R V
5 3 4 syl R V dom R ran R × dom R ran R V
6 unexg R V dom R ran R × dom R ran R V R dom R ran R × dom R ran R V
7 5 6 mpdan R V R dom R ran R × dom R ran R V