Description: Axiom of Replacement using abbreviations. Axiom 39(vi) of Quine p. 284. Compare Exercise 9 of TakeutiZaring p. 29. (Contributed by NM, 10-Sep-2006) Shorten proof and avoid ax-10 , ax-12 . (Revised by SN, 19-Dec-2024)
| Ref | Expression | ||
|---|---|---|---|
| Assertion | funimaexg |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | dffun6 | ||
| 2 | 1 | simprbi | |
| 3 | dfima2 | ||
| 4 | axrep6g | ||
| 5 | 3 4 | eqeltrid | |
| 6 | 2 5 | sylan2 | |
| 7 | 6 | ancoms |