Description: Detach truth from conjunction in biconditional. (Contributed by NM, 27-Feb-1996)
Ref | Expression | ||
---|---|---|---|
Hypotheses | mpbiran.1 | ⊢ 𝜓 | |
mpbiran.2 | ⊢ ( 𝜑 ↔ ( 𝜓 ∧ 𝜒 ) ) | ||
Assertion | mpbiran | ⊢ ( 𝜑 ↔ 𝜒 ) |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | mpbiran.1 | ⊢ 𝜓 | |
2 | mpbiran.2 | ⊢ ( 𝜑 ↔ ( 𝜓 ∧ 𝜒 ) ) | |
3 | 1 | biantrur | ⊢ ( 𝜒 ↔ ( 𝜓 ∧ 𝜒 ) ) |
4 | 2 3 | bitr4i | ⊢ ( 𝜑 ↔ 𝜒 ) |