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| Description: Define a one-to-one function. For equivalent definitions see dff12 3771 and dff13 3988. 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 3260 |
. 2
|
| 5 | 1, 2, 3 | wf 3259 |
. . 3
|
| 6 | 3 | ccnv 3250 |
. . . 4
|
| 7 | 6 | wfun 3257 |
. . 3
|
| 8 | 5, 7 | wa 221 |
. 2
|
| 9 | 4, 8 | wb 144 |
1
|
| Colors of variables: wff set class |
| This definition is referenced by: f1eq1 3767 f1eq2 3768 f1eq3 3769 hbf1 3770 dff12 3771 f1f 3772 f1cnv 3773 f1co 3774 dff1o2 3801 dff1o3 3802 f1f1orn 3807 f1ores 3811 f1imacnv 3813 f11o 3823 f10 3824 tz7.48lem 4256 abianfp 4263 ssdomg 4549 sbthlem9 4600 fodomr 4628 inf3lem7 4764 fodom 4944 reeff1o 7634 infxpidmlem7 7770 hmeogrp 11044 hartoglem 11435 |