Theorem eldifad 3211

Description: If a class is in the difference of two classes, it is also in the minuend. One-way deduction form of eldif 3209. (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 3209	. . 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 2202   ∖ cdif 3197

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 619  ax-in2 620  ax-io 716  ax-5 1495  ax-7 1496  ax-gen 1497  ax-ie1 1541  ax-ie2 1542  ax-8 1552  ax-10 1553  ax-11 1554  ax-i12 1555  ax-bndl 1557  ax-4 1558  ax-17 1574  ax-i9 1578  ax-ial 1582  ax-i5r 1583  ax-ext 2213

This theorem depends on definitions:  df-bi 117  df-tru 1400  df-nf 1509  df-sb 1811  df-clab 2218  df-cleq 2224  df-clel 2227  df-nfc 2363  df-v 2804  df-dif 3202

This theorem is referenced by:  fimax2gtri  7090  finexdc  7091  elssdc  7093  unfidisj  7113  undifdc  7115  ssfirab  7128  fnfi  7134  iunfidisj  7144  dcfi  7179  hashunlem  11066  zfz1isolemiso  11102  fsumrelem  12031  fprodcl2lem  12165  fprodap0  12181  fprodrec  12189  fprodap0f  12196  fprodle  12200  iuncld  14838  fsumcncntop  15290  gausslemma2dlem0i  15785  gausslemma2dlem4  15792  gausslemma2dlem5a  15793  gausslemma2dlem7  15796  lgseisenlem1  15798  lgseisenlem2  15799  lgseisenlem3  15800  lgseisenlem4  15801  lgseisen  15802  lgsquadlem1  15805  lgsquadlem2  15806  lgsquadlem3  15807  1loopgrvd0fi  16156  bj-charfun  16402