Theorem eldifd 3176

Description: If a class is in one class and not another, it is also in their difference. One-way deduction form of eldif 3175. (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 3175	. 2 ⊢ (𝐴 ∈ (𝐵 ∖ 𝐶) ↔ (𝐴 ∈ 𝐵 ∧ ¬ 𝐴 ∈ 𝐶))
4	1, 2, 3	sylanbrc 417	1 ⊢ (𝜑 → 𝐴 ∈ (𝐵 ∖ 𝐶))

Syntax hints:  ¬ wn 3   → wi 4   ∈ wcel 2176   ∖ cdif 3163

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 615  ax-in2 616  ax-io 711  ax-5 1470  ax-7 1471  ax-gen 1472  ax-ie1 1516  ax-ie2 1517  ax-8 1527  ax-10 1528  ax-11 1529  ax-i12 1530  ax-bndl 1532  ax-4 1533  ax-17 1549  ax-i9 1553  ax-ial 1557  ax-i5r 1558  ax-ext 2187

This theorem depends on definitions:  df-bi 117  df-tru 1376  df-nf 1484  df-sb 1786  df-clab 2192  df-cleq 2198  df-clel 2201  df-nfc 2337  df-v 2774  df-dif 3168

This theorem is referenced by:  exmidundif  4250  exmidundifim  4251  frirrg  4397  dcdifsnid  6590  phpelm  6963  findcard2d  6988  findcard2sd  6989  diffifi  6991  unsnfidcex  7017  unsnfidcel  7018  undifdcss  7020  difinfsnlem  7201  difinfsn  7202  hashunlem  10949  seq3coll  10987  fsum3cvg  11689  isumss  11702  fisumss  11703  fproddccvg  11883  fprodssdc  11901  sqrt2irr0  12486  nnoddn2prmb  12585  logbgcd1irr  15439  2lgslem2  15569