Theorem eldifad 3208

Description: If a class is in the difference of two classes, it is also in the minuend. One-way deduction form of eldif 3206. (Contributed by David Moews, 1-May-2017.)

Hypothesis

Ref	Expression
eldifad.1	⊢ (𝜑 → 𝐴 ∈ (𝐵 ∖ 𝐶))

Assertion

Ref	Expression
eldifad	⊢ (𝜑 → 𝐴 ∈ 𝐵)

Proof of Theorem eldifad

Step	Hyp	Ref	Expression
1		eldifad.1	. . 3 ⊢ (𝜑 → 𝐴 ∈ (𝐵 ∖ 𝐶))
2		eldif 3206	. . 3 ⊢ (𝐴 ∈ (𝐵 ∖ 𝐶) ↔ (𝐴 ∈ 𝐵 ∧ ¬ 𝐴 ∈ 𝐶))
3	1, 2	sylib 122	. 2 ⊢ (𝜑 → (𝐴 ∈ 𝐵 ∧ ¬ 𝐴 ∈ 𝐶))
4	3	simpld 112	1 ⊢ (𝜑 → 𝐴 ∈ 𝐵)

Syntax hints:  ¬ wn 3   → wi 4   ∧ wa 104   ∈ wcel 2200   ∖ cdif 3194

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 617  ax-in2 618  ax-io 714  ax-5 1493  ax-7 1494  ax-gen 1495  ax-ie1 1539  ax-ie2 1540  ax-8 1550  ax-10 1551  ax-11 1552  ax-i12 1553  ax-bndl 1555  ax-4 1556  ax-17 1572  ax-i9 1576  ax-ial 1580  ax-i5r 1581  ax-ext 2211

This theorem depends on definitions:  df-bi 117  df-tru 1398  df-nf 1507  df-sb 1809  df-clab 2216  df-cleq 2222  df-clel 2225  df-nfc 2361  df-v 2801  df-dif 3199

This theorem is referenced by:  fimax2gtri  7059  finexdc  7060  unfidisj  7080  undifdc  7082  ssfirab  7094  fnfi  7099  iunfidisj  7109  dcfi  7144  hashunlem  11021  zfz1isolemiso  11056  fsumrelem  11977  fprodcl2lem  12111  fprodap0  12127  fprodrec  12135  fprodap0f  12142  fprodle  12146  iuncld  14783  fsumcncntop  15235  gausslemma2dlem0i  15730  gausslemma2dlem4  15737  gausslemma2dlem5a  15738  gausslemma2dlem7  15741  lgseisenlem1  15743  lgseisenlem2  15744  lgseisenlem3  15745  lgseisenlem4  15746  lgseisen  15747  lgsquadlem1  15750  lgsquadlem2  15751  lgsquadlem3  15752  bj-charfun  16128