| Metamath Proof Explorer |
< Previous
Next >
Related theorems Unicode version |
| Description: The antecedent provides a condition implying the converse of 19.33 1091. Compare Theorem 19.33 of [Margaris] p. 90. |
| Ref | Expression |
|---|---|
| 19.33b |
|
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | ianor 305 |
. . . 4
| |
| 2 | alnex 1033 |
. . . . 5
| |
| 3 | alnex 1033 |
. . . . 5
| |
| 4 | 2, 3 | orbi12i 257 |
. . . 4
|
| 5 | 1, 4 | bitr4 176 |
. . 3
|
| 6 | biorf 735 |
. . . . . . 7
| |
| 7 | 6 | 19.20i 992 |
. . . . . 6
|
| 8 | 19.15 997 |
. . . . . 6
| |
| 9 | 7, 8 | syl 10 |
. . . . 5
|
| 10 | olc 268 |
. . . . 5
| |
| 11 | 9, 10 | syl6bir 215 |
. . . 4
|
| 12 | biorf 735 |
. . . . . . . 8
| |
| 13 | orcom 246 |
. . . . . . . 8
| |
| 14 | 12, 13 | syl6bb 536 |
. . . . . . 7
|
| 15 | 14 | 19.20i 992 |
. . . . . 6
|
| 16 | 19.15 997 |
. . . . . 6
| |
| 17 | 15, 16 | syl 10 |
. . . . 5
|
| 18 | orc 269 |
. . . . 5
| |
| 19 | 17, 18 | syl6bir 215 |
. . . 4
|
| 20 | 11, 19 | jaoi 341 |
. . 3
|
| 21 | 5, 20 | sylbi 199 |
. 2
|
| 22 | 19.33 1091 |
. 2
| |
| 23 | 21, 22 | impbid1 517 |
1
|
| Colors of variables: wff set class |
| Syntax hints: |
| This theorem is referenced by: kmlem16 4780 |
| This theorem was proved from axioms: ax-1 4 ax-2 5 ax-3 6 ax-mp 7 ax-gen 963 ax-4 973 ax-5o 975 |
| This theorem depends on definitions: df-bi 147 df-or 224 df-an 225 df-ex 981 |