Description: Biconditional form of expcomd . (Contributed by Alan Sare, 22-Jul-2012) (New usage is discouraged.)
| Ref | Expression | ||
|---|---|---|---|
| Assertion | expcomdg | ⊢ ( ( 𝜑 → ( ( 𝜓 ∧ 𝜒 ) → 𝜃 ) ) ↔ ( 𝜑 → ( 𝜒 → ( 𝜓 → 𝜃 ) ) ) ) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | ancomst | ⊢ ( ( ( 𝜓 ∧ 𝜒 ) → 𝜃 ) ↔ ( ( 𝜒 ∧ 𝜓 ) → 𝜃 ) ) | |
| 2 | impexp | ⊢ ( ( ( 𝜒 ∧ 𝜓 ) → 𝜃 ) ↔ ( 𝜒 → ( 𝜓 → 𝜃 ) ) ) | |
| 3 | 1 2 | bitri | ⊢ ( ( ( 𝜓 ∧ 𝜒 ) → 𝜃 ) ↔ ( 𝜒 → ( 𝜓 → 𝜃 ) ) ) |
| 4 | 3 | imbi2i | ⊢ ( ( 𝜑 → ( ( 𝜓 ∧ 𝜒 ) → 𝜃 ) ) ↔ ( 𝜑 → ( 𝜒 → ( 𝜓 → 𝜃 ) ) ) ) |