This is an inofficial mirror of http://metamath.tirix.org for personal testing of a visualizer extension only.
Description: Deduction form of Theorem 19.22 of Margaris p. 90, see exim . (Contributed by NM, 29-Jun-1993) (Revised by Mario Carneiro, 24-Sep-2016)
| Ref | Expression | ||
|---|---|---|---|
| Hypotheses | eximd.1 | ⊢ Ⅎ 𝑥 𝜑 | |
| eximd.2 | ⊢ ( 𝜑 → ( 𝜓 → 𝜒 ) ) | ||
| Assertion | eximd | ⊢ ( 𝜑 → ( ∃ 𝑥 𝜓 → ∃ 𝑥 𝜒 ) ) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | eximd.1 | ⊢ Ⅎ 𝑥 𝜑 | |
| 2 | eximd.2 | ⊢ ( 𝜑 → ( 𝜓 → 𝜒 ) ) | |
| 3 | 1 | nf5ri | ⊢ ( 𝜑 → ∀ 𝑥 𝜑 ) |
| 4 | 3 2 | eximdh | ⊢ ( 𝜑 → ( ∃ 𝑥 𝜓 → ∃ 𝑥 𝜒 ) ) |