Theorem neeq2 2391

Description: Equality theorem for inequality. (Contributed by NM, 19-Nov-1994.)

Assertion

Ref	Expression
neeq2	⊢ (𝐴 = 𝐵 → (𝐶 ≠ 𝐴 ↔ 𝐶 ≠ 𝐵))

Proof of Theorem neeq2

Step	Hyp	Ref	Expression
1		eqeq2 2216	. . 3 ⊢ (𝐴 = 𝐵 → (𝐶 = 𝐴 ↔ 𝐶 = 𝐵))
2	1	notbid 669	. 2 ⊢ (𝐴 = 𝐵 → (¬ 𝐶 = 𝐴 ↔ ¬ 𝐶 = 𝐵))
3		df-ne 2378	. 2 ⊢ (𝐶 ≠ 𝐴 ↔ ¬ 𝐶 = 𝐴)
4		df-ne 2378	. 2 ⊢ (𝐶 ≠ 𝐵 ↔ ¬ 𝐶 = 𝐵)
5	2, 3, 4	3bitr4g 223	1 ⊢ (𝐴 = 𝐵 → (𝐶 ≠ 𝐴 ↔ 𝐶 ≠ 𝐵))

Syntax hints:  ¬ wn 3   → wi 4   ↔ wb 105   = wceq 1373   ≠ wne 2377

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-5 1471  ax-gen 1473  ax-4 1534  ax-17 1550  ax-ext 2188

This theorem depends on definitions:  df-bi 117  df-cleq 2199  df-ne 2378

This theorem is referenced by:  neeq2i  2393  neeq2d  2396  disji2  4043  fodjuomnilemdc  7261  netap  7386  2oneel  7388  2omotaplemap  7389  2omotaplemst  7390  exmidapne  7392  xrlttri3  9939  hashdmprop2dom  11011  fun2dmnop0  11014  isnzr2  14021  neapmkv  16148  neap0mkv  16149  ltlenmkv  16150