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| Description: Define a one-to-one function. For equivalent definitions see dff12 4609 and dff13 4850. Compare Definition 6.15(5) of [TakeutiZaring] p. 27. We use their notation ("1-1" above the arrow). |
| Ref | Expression |
|---|---|
| df-f1 |
|
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | cA |
. . 3
| |
| 2 | cB |
. . 3
| |
| 3 | cF |
. . 3
| |
| 4 | 1, 2, 3 | wf1 3995 |
. 2
|
| 5 | 1, 2, 3 | wf 3994 |
. . 3
|
| 6 | 3 | ccnv 3985 |
. . . 4
|
| 7 | 6 | wfun 3992 |
. . 3
|
| 8 | 5, 7 | wa 240 |
. 2
|
| 9 | 4, 8 | wb 163 |
1
|
| Colors of variables: wff set class |
| This definition is referenced by: f1eq1 4605 f1eq2 4606 f1eq3 4607 hbf1 4608 dff12 4609 f1f 4610 f1cnv 4611 f1co 4612 dff1o2 4639 dff1o2OLD 4640 dff1o3OLD 4642 f1f1orn 4649 f1ores 4654 f1imacnv 4656 f11o 4666 f10 4667 tz7.48lem 5164 abianfp 5171 ssdomg 5467 sbthlem9 5518 fodomr 5547 hartoglem 5692 inf3lem7 5725 fodom 5960 reeff1o 8691 infxpidmlem7 8827 injrec2 14466 hmeogrp 14892 hartoglemOLD 15383 |