Metamath Proof Explorer


Definition df-redundp

Description: Define the redundancy operator for propositions, cf. df-redund . (Contributed by Peter Mazsa, 23-Oct-2022)

Ref Expression
Assertion df-redundp ( redund ( 𝜑 , 𝜓 , 𝜒 ) ↔ ( ( 𝜑 → 𝜓 ) ∧ ( ( 𝜑 ∧ 𝜒 ) ↔ ( 𝜓 ∧ 𝜒 ) ) ) )

Detailed syntax breakdown

Step Hyp Ref Expression
0 wph ⊢ 𝜑
1 wps ⊢ 𝜓
2 wch ⊢ 𝜒
3 0 1 2 wredundp ⊢ redund ( 𝜑 , 𝜓 , 𝜒 )
4 0 1 wi ⊢ ( 𝜑 → 𝜓 )
5 0 2 wa ⊢ ( 𝜑 ∧ 𝜒 )
6 1 2 wa ⊢ ( 𝜓 ∧ 𝜒 )
7 5 6 wb ⊢ ( ( 𝜑 ∧ 𝜒 ) ↔ ( 𝜓 ∧ 𝜒 ) )
8 4 7 wa ⊢ ( ( 𝜑 → 𝜓 ) ∧ ( ( 𝜑 ∧ 𝜒 ) ↔ ( 𝜓 ∧ 𝜒 ) ) )
9 3 8 wb ⊢ ( redund ( 𝜑 , 𝜓 , 𝜒 ) ↔ ( ( 𝜑 → 𝜓 ) ∧ ( ( 𝜑 ∧ 𝜒 ) ↔ ( 𝜓 ∧ 𝜒 ) ) ) )