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  7077  finexdc  7078  elssdc  7080  unfidisj  7100  undifdc  7102  ssfirab  7114  fnfi  7119  iunfidisj  7129  dcfi  7164  hashunlem  11043  zfz1isolemiso  11079  fsumrelem  12003  fprodcl2lem  12137  fprodap0  12153  fprodrec  12161  fprodap0f  12168  fprodle  12172  iuncld  14810  fsumcncntop  15262  gausslemma2dlem0i  15757  gausslemma2dlem4  15764  gausslemma2dlem5a  15765  gausslemma2dlem7  15768  lgseisenlem1  15770  lgseisenlem2  15771  lgseisenlem3  15772  lgseisenlem4  15773  lgseisen  15774  lgsquadlem1  15777  lgsquadlem2  15778  lgsquadlem3  15779  bj-charfun  16279