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Metamath Proof Explorer

Theorem fnerel

Description: Fineness is a relation. (Contributed by Jeff Hankins, 28-Sep-2009)

		Ref	Expression
	Assertion	fnerel	$⊢ Rel Fne$

Step	Hyp	Ref	Expression
1		df-fne	$⊢ Fne = \{⟨x, y⟩ \| (⋃ x = ⋃ y \land \forall z \in x z \subseteq ⋃ (y \cap 𝒫 z))\}$
2	1	relopabiv	$⊢ Rel Fne$