Intuitionistic Logic Explorer |
< Previous
Next >
Nearby theorems |
||
Mirrors > Home > ILE Home > Th. List > 3anbi123i | GIF version |
Description: Join 3 biconditionals with conjunction. (Contributed by NM, 21-Apr-1994.) |
Ref | Expression |
---|---|
bi3.1 | ⊢ (𝜑 ↔ 𝜓) |
bi3.2 | ⊢ (𝜒 ↔ 𝜃) |
bi3.3 | ⊢ (𝜏 ↔ 𝜂) |
Ref | Expression |
---|---|
3anbi123i | ⊢ ((𝜑 ∧ 𝜒 ∧ 𝜏) ↔ (𝜓 ∧ 𝜃 ∧ 𝜂)) |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | bi3.1 | . . . 4 ⊢ (𝜑 ↔ 𝜓) | |
2 | bi3.2 | . . . 4 ⊢ (𝜒 ↔ 𝜃) | |
3 | 1, 2 | anbi12i 457 | . . 3 ⊢ ((𝜑 ∧ 𝜒) ↔ (𝜓 ∧ 𝜃)) |
4 | bi3.3 | . . 3 ⊢ (𝜏 ↔ 𝜂) | |
5 | 3, 4 | anbi12i 457 | . 2 ⊢ (((𝜑 ∧ 𝜒) ∧ 𝜏) ↔ ((𝜓 ∧ 𝜃) ∧ 𝜂)) |
6 | df-3an 975 | . 2 ⊢ ((𝜑 ∧ 𝜒 ∧ 𝜏) ↔ ((𝜑 ∧ 𝜒) ∧ 𝜏)) | |
7 | df-3an 975 | . 2 ⊢ ((𝜓 ∧ 𝜃 ∧ 𝜂) ↔ ((𝜓 ∧ 𝜃) ∧ 𝜂)) | |
8 | 5, 6, 7 | 3bitr4i 211 | 1 ⊢ ((𝜑 ∧ 𝜒 ∧ 𝜏) ↔ (𝜓 ∧ 𝜃 ∧ 𝜂)) |
Colors of variables: wff set class |
Syntax hints: ∧ wa 103 ↔ wb 104 ∧ w3a 973 |
This theorem was proved from axioms: ax-mp 5 ax-1 6 ax-2 7 ax-ia1 105 ax-ia2 106 ax-ia3 107 |
This theorem depends on definitions: df-bi 116 df-3an 975 |
This theorem is referenced by: 3anbi1i 1185 3anbi2i 1186 3anbi3i 1187 syl3anb 1276 ne3anior 2428 isstructim 12417 |
Copyright terms: Public domain | W3C validator |