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Related theorems GIF version |
| Description: Define restricted existential uniqueness. |
| Ref | Expression |
|---|---|
| df-reu | ⊢ (∃!x ∈ A φ ↔ ∃!x(x ∈ A ⋀ φ)) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | wph | . . 3 wff φ | |
| 2 | vx | . . 3 set x | |
| 3 | cA | . . 3 class A | |
| 4 | 1, 2, 3 | wreu 1693 | . 2 wff ∃!x ∈ A φ |
| 5 | 2 | cv 991 | . . . . 5 class x |
| 6 | 5, 3 | wcel 994 | . . . 4 wff x ∈ A |
| 7 | 6, 1 | wa 221 | . . 3 wff (x ∈ A ⋀ φ) |
| 8 | 7, 2 | weu 1419 | . 2 wff ∃!x(x ∈ A ⋀ φ) |
| 9 | 4, 8 | wb 144 | 1 wff (∃!x ∈ A φ ↔ ∃!x(x ∈ A ⋀ φ)) |
| Colors of variables: wff set class |
| This definition is referenced by: hbreu1 1814 reubidva 1825 reubiia 1827 reueq1f 1831 cbvreuv 1848 reurex 1974 reu5 1975 reu2 1976 reu3 1977 reu6 1978 2reuswap 1983 reuss2 2327 reuun2 2330 reupick 2331 reucl 2584 reuuni1 3106 reusn 3115 reuxfr 3127 reuhyp 3128 funcnv3 3663 feu 3754 dff4 3932 fsn 3948 aceq1 4875 aceq6b 4888 supxrre 6251 zmin 6391 climreu 7304 isumclimtfi 7399 pjtheu 9512 neibastop3 11585 ufileu 11658 uptx 11978 |