HomeHome Metamath Proof Explorer < Previous   Next >
Related theorems
GIF version

Theorem difin 1670
Description: Difference with intersection. Theorem 33 of [Suppes] p. 29.
Assertion
Ref Expression
difin (A ∖ (AB)) = (AB)

Proof of Theorem difin
StepHypRef Expression
1 abai 366 . . . 4 ((xA ∧ ¬ xB) ↔ (xA ∧ (xA → ¬ xB)))
2 imnan 207 . . . . 5 ((xA → ¬ xB) ↔ ¬ (xAxB))
32anbi2i 367 . . . 4 ((xA ∧ (xA → ¬ xB)) ↔ (xA ∧ ¬ (xAxB)))
41, 3bitr 151 . . 3 ((xA ∧ ¬ xB) ↔ (xA ∧ ¬ (xAxB)))
5 eldif 1496 . . 3 (x ∈ (AB) ↔ (xA ∧ ¬ xB))
6 eldif 1496 . . . 4 (x ∈ (A ∖ (AB)) ↔ (xA ∧ ¬ x ∈ (AB)))
7 elin 1635 . . . . . 6 (x ∈ (AB) ↔ (xAxB))
87negbii 162 . . . . 5 x ∈ (AB) ↔ ¬ (xAxB))
98anbi2i 367 . . . 4 ((xA ∧ ¬ x ∈ (AB)) ↔ (xA ∧ ¬ (xAxB)))
106, 9bitr 151 . . 3 (x ∈ (A ∖ (AB)) ↔ (xA ∧ ¬ (xAxB)))
114, 5, 103bitr4r 159 . 2 (x ∈ (A ∖ (AB)) ↔ x ∈ (AB))
1211cleqri 1101 1 (A ∖ (AB)) = (AB)
Colors of variables: wff set class
Syntax hints:  ¬ wn 1   → wi 2   ∧ wa 196   = wceq 1091   ∈ wcel 1092   ∖ cdif 1484   ∩ cin 1486
This theorem is referenced by:  dfin4 1673  indif 1675  symdif1 1689  dfsdom2 3362
This theorem was proved from axioms:  ax-1 3  ax-2 4  ax-3 5  ax-mp 6  ax-4 673  ax-5 674  ax-6 675  ax-7 676  ax-gen 677  ax-8 798  ax-9 799  ax-10 800  ax-11 801  ax-12 802  ax-16 922  ax-17 925  ax-ext 1074
This theorem depends on definitions:  df-bi 128  df-an 198  df-ex 679  df-sb 853  df-clab 1093  df-cleq 1097  df-clel 1099  df-v 1349  df-dif 1489  df-in 1491
metamath.org