Description: Double commutation in conjunction. (Contributed by Peter Mazsa, 27-Jun-2019)
Ref | Expression | ||
---|---|---|---|
Assertion | an2anr | ⊢ ( ( ( 𝜑 ∧ 𝜓 ) ∧ ( 𝜒 ∧ 𝜃 ) ) ↔ ( ( 𝜓 ∧ 𝜑 ) ∧ ( 𝜃 ∧ 𝜒 ) ) ) |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | ancom | ⊢ ( ( 𝜑 ∧ 𝜓 ) ↔ ( 𝜓 ∧ 𝜑 ) ) | |
2 | ancom | ⊢ ( ( 𝜒 ∧ 𝜃 ) ↔ ( 𝜃 ∧ 𝜒 ) ) | |
3 | 1 2 | anbi12i | ⊢ ( ( ( 𝜑 ∧ 𝜓 ) ∧ ( 𝜒 ∧ 𝜃 ) ) ↔ ( ( 𝜓 ∧ 𝜑 ) ∧ ( 𝜃 ∧ 𝜒 ) ) ) |