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Description: Formula-building rule for restricted at-most-one quantifier (deduction form). (Contributed by NM, 16-Jun-2017)
| Ref | Expression | ||
|---|---|---|---|
| Hypothesis | rmobidv.1 | ⊢ ( 𝜑 → ( 𝜓 ↔ 𝜒 ) ) | |
| Assertion | rmobidv | ⊢ ( 𝜑 → ( ∃* 𝑥 ∈ 𝐴 𝜓 ↔ ∃* 𝑥 ∈ 𝐴 𝜒 ) ) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | rmobidv.1 | ⊢ ( 𝜑 → ( 𝜓 ↔ 𝜒 ) ) | |
| 2 | 1 | adantr | ⊢ ( ( 𝜑 ∧ 𝑥 ∈ 𝐴 ) → ( 𝜓 ↔ 𝜒 ) ) |
| 3 | 2 | rmobidva | ⊢ ( 𝜑 → ( ∃* 𝑥 ∈ 𝐴 𝜓 ↔ ∃* 𝑥 ∈ 𝐴 𝜒 ) ) |