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Metamath Proof Explorer

Theorem bnj1113

Description: First-order logic and set theory. (Contributed by Jonathan Ben-Naim, 3-Jun-2011) (New usage is discouraged.)

		Ref	Expression
	Hypothesis	bnj1113.1	$⊢ A = B \to C = D$
	Assertion	bnj1113	$⊢ A = B \to ⋃_{x \in C} E = ⋃_{x \in D} E$

Step	Hyp	Ref	Expression
1		bnj1113.1	$⊢ A = B \to C = D$
2	1	iuneq1d	$⊢ A = B \to ⋃_{x \in C} E = ⋃_{x \in D} E$