Theorem neeq1i 2271

Description: Inference for inequality. (Contributed by NM, 29-Apr-2005.)

Hypothesis

Ref	Expression
neeq1i.1	⊢ 𝐴 = 𝐵

Assertion

Ref	Expression
neeq1i	⊢ (𝐴 ≠ 𝐶 ↔ 𝐵 ≠ 𝐶)

Proof of Theorem neeq1i

Step	Hyp	Ref	Expression
1		neeq1i.1	. 2 ⊢ 𝐴 = 𝐵
2		neeq1 2269	. 2 ⊢ (𝐴 = 𝐵 → (𝐴 ≠ 𝐶 ↔ 𝐵 ≠ 𝐶))
3	1, 2	ax-mp 7	1 ⊢ (𝐴 ≠ 𝐶 ↔ 𝐵 ≠ 𝐶)

Syntax hints:   ↔ wb 104   = wceq 1290   ≠ wne 2256

This theorem was proved from axioms:  ax-1 5  ax-2 6  ax-mp 7  ax-ia1 105  ax-ia2 106  ax-ia3 107  ax-in1 580  ax-in2 581  ax-5 1382  ax-gen 1384  ax-4 1446  ax-17 1465  ax-ext 2071

This theorem depends on definitions:  df-bi 116  df-cleq 2082  df-ne 2257

This theorem is referenced by:  neeq12i  2273  eqnetri  2279  syl5eqner  2287  rabn0r  3313