Metamath Proof Explorer


Definition df-ne

Description: Define inequality. (Contributed by NM, 26-May-1993)

Ref Expression
Assertion df-ne ( 𝐴 ≠ 𝐵 ↔ ¬ 𝐴 = 𝐵 )

Detailed syntax breakdown

Step Hyp Ref Expression
0 cA ⊢ 𝐴
1 cB ⊢ 𝐵
2 0 1 wne ⊢ 𝐴 ≠ 𝐵
3 0 1 wceq ⊢ 𝐴 = 𝐵
4 3 wn ⊢ ¬ 𝐴 = 𝐵
5 2 4 wb ⊢ ( 𝐴 ≠ 𝐵 ↔ ¬ 𝐴 = 𝐵 )