Description: Commutative law for a conjunction with a triple conjunction: second and forth positions interchanged. (Contributed by AV, 18-Feb-2022)
| Ref | Expression | ||
|---|---|---|---|
| Assertion | 3an4ancom24 | ⊢ ( ( ( 𝜑 ∧ 𝜓 ∧ 𝜒 ) ∧ 𝜃 ) ↔ ( ( 𝜑 ∧ 𝜃 ∧ 𝜒 ) ∧ 𝜓 ) ) | 
| Step | Hyp | Ref | Expression | 
|---|---|---|---|
| 1 | an4com24 | ⊢ ( ( ( 𝜑 ∧ 𝜓 ) ∧ ( 𝜒 ∧ 𝜃 ) ) ↔ ( ( 𝜑 ∧ 𝜃 ) ∧ ( 𝜒 ∧ 𝜓 ) ) ) | |
| 2 | 3an4anass | ⊢ ( ( ( 𝜑 ∧ 𝜓 ∧ 𝜒 ) ∧ 𝜃 ) ↔ ( ( 𝜑 ∧ 𝜓 ) ∧ ( 𝜒 ∧ 𝜃 ) ) ) | |
| 3 | 3an4anass | ⊢ ( ( ( 𝜑 ∧ 𝜃 ∧ 𝜒 ) ∧ 𝜓 ) ↔ ( ( 𝜑 ∧ 𝜃 ) ∧ ( 𝜒 ∧ 𝜓 ) ) ) | |
| 4 | 1 2 3 | 3bitr4i | ⊢ ( ( ( 𝜑 ∧ 𝜓 ∧ 𝜒 ) ∧ 𝜃 ) ↔ ( ( 𝜑 ∧ 𝜃 ∧ 𝜒 ) ∧ 𝜓 ) ) |