Theorem in0 3455

Description: The intersection of a class with the empty set is the empty set. Theorem 16 of [Suppes] p. 26. (Contributed by NM, 5-Aug-1993.)

Assertion

Ref	Expression
in0	⊢ (𝐴 ∩ ∅) = ∅

Proof of Theorem in0

Dummy variable 𝑥 is distinct from all other variables.

Step	Hyp	Ref	Expression
1		noel 3424	. . . 4 ⊢ ¬ 𝑥 ∈ ∅
2	1	bianfi 947	. . 3 ⊢ (𝑥 ∈ ∅ ↔ (𝑥 ∈ 𝐴 ∧ 𝑥 ∈ ∅))
3	2	bicomi 132	. 2 ⊢ ((𝑥 ∈ 𝐴 ∧ 𝑥 ∈ ∅) ↔ 𝑥 ∈ ∅)
4	3	ineqri 3326	1 ⊢ (𝐴 ∩ ∅) = ∅

Syntax hints:   ∧ wa 104   = wceq 1353   ∈ wcel 2146   ∩ cin 3126  ∅c0 3420

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 106  ax-ia2 107  ax-ia3 108  ax-in1 614  ax-in2 615  ax-io 709  ax-5 1445  ax-7 1446  ax-gen 1447  ax-ie1 1491  ax-ie2 1492  ax-8 1502  ax-10 1503  ax-11 1504  ax-i12 1505  ax-bndl 1507  ax-4 1508  ax-17 1524  ax-i9 1528  ax-ial 1532  ax-i5r 1533  ax-ext 2157

This theorem depends on definitions:  df-bi 117  df-tru 1356  df-nf 1459  df-sb 1761  df-clab 2162  df-cleq 2168  df-clel 2171  df-nfc 2306  df-v 2737  df-dif 3129  df-in 3133  df-nul 3421

This theorem is referenced by:  0in  3456  res0  4904  dju0en  7203  rest0  13250