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Metamath Proof Explorer

Theorem relcoss

Description: Cosets by R is a relation. (Contributed by Peter Mazsa, 27-Dec-2018)

		Ref	Expression
	Assertion	relcoss	$⊢ Rel ≀ R$

Step	Hyp	Ref	Expression
1		df-coss	$⊢ ≀ R = \{⟨x, y⟩ \| \exists u (u R x \land u R y)\}$
2	1	relopabiv	$⊢ Rel ≀ R$