Theorem eldifd 3126

Description: If a class is in one class and not another, it is also in their difference. One-way deduction form of eldif 3125. (Contributed by David Moews, 1-May-2017.)

Hypotheses

Ref	Expression
eldifd.1	⊢ (𝜑 → 𝐴 ∈ 𝐵)
eldifd.2	⊢ (𝜑 → ¬ 𝐴 ∈ 𝐶)

Assertion

Ref	Expression
eldifd	⊢ (𝜑 → 𝐴 ∈ (𝐵 ∖ 𝐶))

Proof of Theorem eldifd

Step	Hyp	Ref	Expression
1		eldifd.1	. 2 ⊢ (𝜑 → 𝐴 ∈ 𝐵)
2		eldifd.2	. 2 ⊢ (𝜑 → ¬ 𝐴 ∈ 𝐶)
3		eldif 3125	. 2 ⊢ (𝐴 ∈ (𝐵 ∖ 𝐶) ↔ (𝐴 ∈ 𝐵 ∧ ¬ 𝐴 ∈ 𝐶))
4	1, 2, 3	sylanbrc 414	1 ⊢ (𝜑 → 𝐴 ∈ (𝐵 ∖ 𝐶))

Syntax hints:  ¬ wn 3   → wi 4   ∈ wcel 2136   ∖ cdif 3113

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 105  ax-ia2 106  ax-ia3 107  ax-in1 604  ax-in2 605  ax-io 699  ax-5 1435  ax-7 1436  ax-gen 1437  ax-ie1 1481  ax-ie2 1482  ax-8 1492  ax-10 1493  ax-11 1494  ax-i12 1495  ax-bndl 1497  ax-4 1498  ax-17 1514  ax-i9 1518  ax-ial 1522  ax-i5r 1523  ax-ext 2147

This theorem depends on definitions:  df-bi 116  df-tru 1346  df-nf 1449  df-sb 1751  df-clab 2152  df-cleq 2158  df-clel 2161  df-nfc 2297  df-v 2728  df-dif 3118

This theorem is referenced by:  exmidundif  4185  exmidundifim  4186  frirrg  4328  dcdifsnid  6472  phpelm  6832  findcard2d  6857  findcard2sd  6858  diffifi  6860  unsnfidcex  6885  unsnfidcel  6886  undifdcss  6888  difinfsnlem  7064  difinfsn  7065  hashunlem  10717  seq3coll  10755  fsum3cvg  11319  isumss  11332  fisumss  11333  fproddccvg  11513  fprodssdc  11531  sqrt2irr0  12096  nnoddn2prmb  12194  logbgcd1irr  13525