Description: Inferring a theorem when it is implied by an equality which may be true. (Contributed by BJ, 30-Sep-2018)
Ref | Expression | ||
---|---|---|---|
Hypotheses | exlimiieq1.1 | ⊢ Ⅎ 𝑥 𝜑 | |
exlimiieq1.2 | ⊢ ( 𝑥 = 𝑦 → 𝜑 ) | ||
Assertion | exlimiieq1 | ⊢ 𝜑 |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | exlimiieq1.1 | ⊢ Ⅎ 𝑥 𝜑 | |
2 | exlimiieq1.2 | ⊢ ( 𝑥 = 𝑦 → 𝜑 ) | |
3 | ax6e | ⊢ ∃ 𝑥 𝑥 = 𝑦 | |
4 | 1 2 3 | exlimii | ⊢ 𝜑 |