Description: Distribution of implication over biconditional (deduction form). Variant of pm5.74d . (Contributed by NM, 4-May-2007)
Ref | Expression | ||
---|---|---|---|
Hypothesis | pm5.74da.1 | ⊢ ( ( 𝜑 ∧ 𝜓 ) → ( 𝜒 ↔ 𝜃 ) ) | |
Assertion | pm5.74da | ⊢ ( 𝜑 → ( ( 𝜓 → 𝜒 ) ↔ ( 𝜓 → 𝜃 ) ) ) |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | pm5.74da.1 | ⊢ ( ( 𝜑 ∧ 𝜓 ) → ( 𝜒 ↔ 𝜃 ) ) | |
2 | 1 | ex | ⊢ ( 𝜑 → ( 𝜓 → ( 𝜒 ↔ 𝜃 ) ) ) |
3 | 2 | pm5.74d | ⊢ ( 𝜑 → ( ( 𝜓 → 𝜒 ) ↔ ( 𝜓 → 𝜃 ) ) ) |