Intuitionistic Logic Explorer |
< Previous
Next >
Nearby theorems |
||
Mirrors > Home > ILE Home > Th. List > unfiin | Unicode version |
Description: The union of two finite sets is finite if their intersection is. (Contributed by Jim Kingdon, 2-Mar-2022.) |
Ref | Expression |
---|---|
unfiin |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | simpll 518 | . . . . . 6 | |
2 | simpr 109 | . . . . . 6 | |
3 | inss1 3291 | . . . . . . 7 | |
4 | 3 | a1i 9 | . . . . . 6 |
5 | undiffi 6806 | . . . . . 6 | |
6 | 1, 2, 4, 5 | syl3anc 1216 | . . . . 5 |
7 | simplr 519 | . . . . . 6 | |
8 | inss2 3292 | . . . . . . 7 | |
9 | 8 | a1i 9 | . . . . . 6 |
10 | undiffi 6806 | . . . . . 6 | |
11 | 7, 2, 9, 10 | syl3anc 1216 | . . . . 5 |
12 | 6, 11 | uneq12d 3226 | . . . 4 |
13 | unundi 3232 | . . . 4 | |
14 | 12, 13 | syl6eqr 2188 | . . 3 |
15 | diffifi 6781 | . . . . . 6 | |
16 | 1, 2, 4, 15 | syl3anc 1216 | . . . . 5 |
17 | diffifi 6781 | . . . . . 6 | |
18 | 7, 2, 9, 17 | syl3anc 1216 | . . . . 5 |
19 | incom 3263 | . . . . . . . . . 10 | |
20 | 19 | difeq2i 3186 | . . . . . . . . 9 |
21 | difin 3308 | . . . . . . . . 9 | |
22 | 20, 21 | eqtr3i 2160 | . . . . . . . 8 |
23 | 22 | ineq2i 3269 | . . . . . . 7 |
24 | difss 3197 | . . . . . . . 8 | |
25 | disjdif 3430 | . . . . . . . 8 | |
26 | ssdisj 3414 | . . . . . . . 8 | |
27 | 24, 25, 26 | mp2an 422 | . . . . . . 7 |
28 | 23, 27 | eqtri 2158 | . . . . . 6 |
29 | 28 | a1i 9 | . . . . 5 |
30 | unfidisj 6803 | . . . . 5 | |
31 | 16, 18, 29, 30 | syl3anc 1216 | . . . 4 |
32 | difundir 3324 | . . . . . . 7 | |
33 | 32 | ineq2i 3269 | . . . . . 6 |
34 | disjdif 3430 | . . . . . 6 | |
35 | 33, 34 | eqtr3i 2160 | . . . . 5 |
36 | 35 | a1i 9 | . . . 4 |
37 | unfidisj 6803 | . . . 4 | |
38 | 2, 31, 36, 37 | syl3anc 1216 | . . 3 |
39 | 14, 38 | eqeltrd 2214 | . 2 |
40 | 39 | 3impa 1176 | 1 |
Colors of variables: wff set class |
Syntax hints: wi 4 wa 103 w3a 962 wceq 1331 wcel 1480 cdif 3063 cun 3064 cin 3065 wss 3066 c0 3358 cfn 6627 |
This theorem was proved from axioms: ax-mp 5 ax-1 6 ax-2 7 ax-ia1 105 ax-ia2 106 ax-ia3 107 ax-in1 603 ax-in2 604 ax-io 698 ax-5 1423 ax-7 1424 ax-gen 1425 ax-ie1 1469 ax-ie2 1470 ax-8 1482 ax-10 1483 ax-11 1484 ax-i12 1485 ax-bndl 1486 ax-4 1487 ax-13 1491 ax-14 1492 ax-17 1506 ax-i9 1510 ax-ial 1514 ax-i5r 1515 ax-ext 2119 ax-coll 4038 ax-sep 4041 ax-nul 4049 ax-pow 4093 ax-pr 4126 ax-un 4350 ax-setind 4447 ax-iinf 4497 |
This theorem depends on definitions: df-bi 116 df-dc 820 df-3or 963 df-3an 964 df-tru 1334 df-fal 1337 df-nf 1437 df-sb 1736 df-eu 2000 df-mo 2001 df-clab 2124 df-cleq 2130 df-clel 2133 df-nfc 2268 df-ne 2307 df-ral 2419 df-rex 2420 df-reu 2421 df-rab 2423 df-v 2683 df-sbc 2905 df-csb 2999 df-dif 3068 df-un 3070 df-in 3072 df-ss 3079 df-nul 3359 df-if 3470 df-pw 3507 df-sn 3528 df-pr 3529 df-op 3531 df-uni 3732 df-int 3767 df-iun 3810 df-br 3925 df-opab 3985 df-mpt 3986 df-tr 4022 df-id 4210 df-iord 4283 df-on 4285 df-suc 4288 df-iom 4500 df-xp 4540 df-rel 4541 df-cnv 4542 df-co 4543 df-dm 4544 df-rn 4545 df-res 4546 df-ima 4547 df-iota 5083 df-fun 5120 df-fn 5121 df-f 5122 df-f1 5123 df-fo 5124 df-f1o 5125 df-fv 5126 df-1o 6306 df-er 6422 df-en 6628 df-fin 6630 |
This theorem is referenced by: (None) |
Copyright terms: Public domain | W3C validator |