Theorem elint2 4921

Description: Membership in class intersection. (Contributed by NM, 14-Oct-1999.)

Hypothesis

Ref	Expression
elint2.1	⊢ 𝐴 ∈ V

Assertion

Ref	Expression
elint2	⊢ (𝐴 ∈ ∩ 𝐵 ↔ ∀𝑥 ∈ 𝐵 𝐴 ∈ 𝑥)

Distinct variable groups:   𝑥,𝐴   𝑥,𝐵

Proof of Theorem elint2

Step	Hyp	Ref	Expression
1		elint2.1	. . 3 ⊢ 𝐴 ∈ V
2	1	elint 4920	. 2 ⊢ (𝐴 ∈ ∩ 𝐵 ↔ ∀𝑥(𝑥 ∈ 𝐵 → 𝐴 ∈ 𝑥))
3		df-ral 3082	. 2 ⊢ (∀𝑥 ∈ 𝐵 𝐴 ∈ 𝑥 ↔ ∀𝑥(𝑥 ∈ 𝐵 → 𝐴 ∈ 𝑥))
4	2, 3	bitr4i 281	1 ⊢ (𝐴 ∈ ∩ 𝐵 ↔ ∀𝑥 ∈ 𝐵 𝐴 ∈ 𝑥)

This proof depends on syntax axioms:   → wi 4   ↔ wb 209  ∀wal 1568   ∈ wcel 2146  ∀wral 3081  Vcvv 3457  ∩ cint 4914

This proof depends on axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1828  ax-4 1842  ax-5 1943  ax-6 2000  ax-7 2041  ax-8 2148  ax-9 2156  ax-ext 2737

This proof depends on definitions:  df-bi 210  df-an 402  df-tru 1573  df-ex 1813  df-sb 2100  df-clab 2744  df-cleq 2757  df-clel 2840  df-ral 3082  df-int 4915

This theorem is used by:  int0  4929  ssint  4931  intssuni  4937  iinuni  5066  onint  7795  intwun  10737  inttsk  10776  intgru  10816  subgint  19263  subrngint  20711  subrgint  20746  lssintcl  21137  toponmre  23302  alexsubALTlem3  24259  shintcli  31754  chintcli  31756  intlidl  33794  fin2so  38317  intidl  38740  mzpincl  43525  elimaint  44435  elintima  44439  intsal  47104  salgencntex  47117