Description: Distribution of implication over biconditional (deduction form). (Contributed by NM, 25-Dec-2004)
Ref | Expression | ||
---|---|---|---|
Hypothesis | pm5.32d.1 | ⊢ ( 𝜑 → ( 𝜓 → ( 𝜒 ↔ 𝜃 ) ) ) | |
Assertion | pm5.32rd | ⊢ ( 𝜑 → ( ( 𝜒 ∧ 𝜓 ) ↔ ( 𝜃 ∧ 𝜓 ) ) ) |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | pm5.32d.1 | ⊢ ( 𝜑 → ( 𝜓 → ( 𝜒 ↔ 𝜃 ) ) ) | |
2 | 1 | pm5.32d | ⊢ ( 𝜑 → ( ( 𝜓 ∧ 𝜒 ) ↔ ( 𝜓 ∧ 𝜃 ) ) ) |
3 | ancom | ⊢ ( ( 𝜒 ∧ 𝜓 ) ↔ ( 𝜓 ∧ 𝜒 ) ) | |
4 | ancom | ⊢ ( ( 𝜃 ∧ 𝜓 ) ↔ ( 𝜓 ∧ 𝜃 ) ) | |
5 | 2 3 4 | 3bitr4g | ⊢ ( 𝜑 → ( ( 𝜒 ∧ 𝜓 ) ↔ ( 𝜃 ∧ 𝜓 ) ) ) |