This is an inofficial mirror of http://metamath.tirix.org for personal testing of a visualizer extension only.
Description: Theorem *11.42 in WhiteheadRussell p. 163. Theorem 19.40 of Margaris p. 90 with two quantifiers. (Contributed by Andrew Salmon, 24-May-2011)
| Ref | Expression | ||
|---|---|---|---|
| Assertion | 19.40-2 | ⊢ ( ∃ 𝑥 ∃ 𝑦 ( 𝜑 ∧ 𝜓 ) → ( ∃ 𝑥 ∃ 𝑦 𝜑 ∧ ∃ 𝑥 ∃ 𝑦 𝜓 ) ) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | 19.40 | ⊢ ( ∃ 𝑦 ( 𝜑 ∧ 𝜓 ) → ( ∃ 𝑦 𝜑 ∧ ∃ 𝑦 𝜓 ) ) | |
| 2 | 1 | eximi | ⊢ ( ∃ 𝑥 ∃ 𝑦 ( 𝜑 ∧ 𝜓 ) → ∃ 𝑥 ( ∃ 𝑦 𝜑 ∧ ∃ 𝑦 𝜓 ) ) |
| 3 | 19.40 | ⊢ ( ∃ 𝑥 ( ∃ 𝑦 𝜑 ∧ ∃ 𝑦 𝜓 ) → ( ∃ 𝑥 ∃ 𝑦 𝜑 ∧ ∃ 𝑥 ∃ 𝑦 𝜓 ) ) | |
| 4 | 2 3 | syl | ⊢ ( ∃ 𝑥 ∃ 𝑦 ( 𝜑 ∧ 𝜓 ) → ( ∃ 𝑥 ∃ 𝑦 𝜑 ∧ ∃ 𝑥 ∃ 𝑦 𝜓 ) ) |