Intuitionistic Logic Explorer |
< Previous
Next >
Nearby theorems |
||
Mirrors > Home > ILE Home > Th. List > trint | Unicode version |
Description: The intersection of a class of transitive sets is transitive. Exercise 5(b) of [Enderton] p. 73. (Contributed by Scott Fenton, 25-Feb-2011.) |
Ref | Expression |
---|---|
trint |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | dftr3 3858 | . . . . . 6 | |
2 | 1 | ralbii 2330 | . . . . 5 |
3 | 2 | biimpi 113 | . . . 4 |
4 | df-ral 2311 | . . . . . 6 | |
5 | 4 | ralbii 2330 | . . . . 5 |
6 | ralcom4 2576 | . . . . 5 | |
7 | 5, 6 | bitri 173 | . . . 4 |
8 | 3, 7 | sylib 127 | . . 3 |
9 | ralim 2380 | . . . 4 | |
10 | 9 | alimi 1344 | . . 3 |
11 | 8, 10 | syl 14 | . 2 |
12 | dftr3 3858 | . . 3 | |
13 | df-ral 2311 | . . . 4 | |
14 | vex 2560 | . . . . . . 7 | |
15 | 14 | elint2 3622 | . . . . . 6 |
16 | ssint 3631 | . . . . . 6 | |
17 | 15, 16 | imbi12i 228 | . . . . 5 |
18 | 17 | albii 1359 | . . . 4 |
19 | 13, 18 | bitri 173 | . . 3 |
20 | 12, 19 | bitri 173 | . 2 |
21 | 11, 20 | sylibr 137 | 1 |
Colors of variables: wff set class |
Syntax hints: wi 4 wal 1241 wcel 1393 wral 2306 wss 2917 cint 3615 wtr 3854 |
This theorem was proved from axioms: ax-1 5 ax-2 6 ax-mp 7 ax-ia1 99 ax-ia2 100 ax-ia3 101 ax-io 630 ax-5 1336 ax-7 1337 ax-gen 1338 ax-ie1 1382 ax-ie2 1383 ax-8 1395 ax-10 1396 ax-11 1397 ax-i12 1398 ax-bndl 1399 ax-4 1400 ax-17 1419 ax-i9 1423 ax-ial 1427 ax-i5r 1428 ax-ext 2022 |
This theorem depends on definitions: df-bi 110 df-tru 1246 df-nf 1350 df-sb 1646 df-clab 2027 df-cleq 2033 df-clel 2036 df-nfc 2167 df-ral 2311 df-v 2559 df-in 2924 df-ss 2931 df-uni 3581 df-int 3616 df-tr 3855 |
This theorem is referenced by: onintonm 4243 |
Copyright terms: Public domain | W3C validator |