Theorem ssrexv 3332

Description: Existential quantification restricted to a subclass. (Contributed by NM, 11-Jan-2007.)

Assertion

Ref	Expression
ssrexv	⊢ (A ⊆ B → (∃x ∈ A φ → ∃x ∈ B φ))

Distinct variable groups:   x,A   x,B

Allowed substitution hint:   φ(x)

Proof of Theorem ssrexv

Step	Hyp	Ref	Expression
1		ssel 3268	. . 3 ⊢ (A ⊆ B → (x ∈ A → x ∈ B))
2	1	anim1d 547	. 2 ⊢ (A ⊆ B → ((x ∈ A ∧ φ) → (x ∈ B ∧ φ)))
3	2	reximdv2 2724	1 ⊢ (A ⊆ B → (∃x ∈ A φ → ∃x ∈ B φ))

Syntax hints:   → wi 4   ∈ wcel 1710  ∃wrex 2616   ⊆ wss 3258

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1546  ax-5 1557  ax-17 1616  ax-9 1654  ax-8 1675  ax-6 1729  ax-7 1734  ax-11 1746  ax-12 1925  ax-ext 2334

This theorem depends on definitions:  df-bi 177  df-or 359  df-an 360  df-nan 1288  df-tru 1319  df-ex 1542  df-nf 1545  df-sb 1649  df-clab 2340  df-cleq 2346  df-clel 2349  df-nfc 2479  df-rex 2621  df-v 2862  df-nin 3212  df-compl 3213  df-in 3214  df-ss 3260

This theorem is referenced by:  iunss1  3981