![]() |
Metamath Proof Explorer |
< Previous
Next >
Nearby theorems |
|
Mirrors > Home > MPE Home > Th. List > rankxpl | Structured version Visualization version GIF version |
Description: A lower bound on the rank of a Cartesian product. (Contributed by NM, 18-Sep-2006.) |
Ref | Expression |
---|---|
rankxpl.1 | ⊢ 𝐴 ∈ V |
rankxpl.2 | ⊢ 𝐵 ∈ V |
Ref | Expression |
---|---|
rankxpl | ⊢ ((𝐴 × 𝐵) ≠ ∅ → (rank‘(𝐴 ∪ 𝐵)) ⊆ (rank‘(𝐴 × 𝐵))) |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | unixp 6303 | . . 3 ⊢ ((𝐴 × 𝐵) ≠ ∅ → ∪ ∪ (𝐴 × 𝐵) = (𝐴 ∪ 𝐵)) | |
2 | 1 | fveq2d 6910 | . 2 ⊢ ((𝐴 × 𝐵) ≠ ∅ → (rank‘∪ ∪ (𝐴 × 𝐵)) = (rank‘(𝐴 ∪ 𝐵))) |
3 | rankxpl.1 | . . . . . 6 ⊢ 𝐴 ∈ V | |
4 | rankxpl.2 | . . . . . 6 ⊢ 𝐵 ∈ V | |
5 | 3, 4 | xpex 7771 | . . . . 5 ⊢ (𝐴 × 𝐵) ∈ V |
6 | 5 | uniex 7759 | . . . 4 ⊢ ∪ (𝐴 × 𝐵) ∈ V |
7 | 6 | rankuniss 9903 | . . 3 ⊢ (rank‘∪ ∪ (𝐴 × 𝐵)) ⊆ (rank‘∪ (𝐴 × 𝐵)) |
8 | 5 | rankuniss 9903 | . . 3 ⊢ (rank‘∪ (𝐴 × 𝐵)) ⊆ (rank‘(𝐴 × 𝐵)) |
9 | 7, 8 | sstri 4004 | . 2 ⊢ (rank‘∪ ∪ (𝐴 × 𝐵)) ⊆ (rank‘(𝐴 × 𝐵)) |
10 | 2, 9 | eqsstrrdi 4050 | 1 ⊢ ((𝐴 × 𝐵) ≠ ∅ → (rank‘(𝐴 ∪ 𝐵)) ⊆ (rank‘(𝐴 × 𝐵))) |
Colors of variables: wff setvar class |
Syntax hints: → wi 4 ∈ wcel 2105 ≠ wne 2937 Vcvv 3477 ∪ cun 3960 ⊆ wss 3962 ∅c0 4338 ∪ cuni 4911 × cxp 5686 ‘cfv 6562 rankcrnk 9800 |
This theorem was proved from axioms: ax-mp 5 ax-1 6 ax-2 7 ax-3 8 ax-gen 1791 ax-4 1805 ax-5 1907 ax-6 1964 ax-7 2004 ax-8 2107 ax-9 2115 ax-10 2138 ax-11 2154 ax-12 2174 ax-ext 2705 ax-rep 5284 ax-sep 5301 ax-nul 5311 ax-pow 5370 ax-pr 5437 ax-un 7753 ax-reg 9629 ax-inf2 9678 |
This theorem depends on definitions: df-bi 207 df-an 396 df-or 848 df-3or 1087 df-3an 1088 df-tru 1539 df-fal 1549 df-ex 1776 df-nf 1780 df-sb 2062 df-mo 2537 df-eu 2566 df-clab 2712 df-cleq 2726 df-clel 2813 df-nfc 2889 df-ne 2938 df-ral 3059 df-rex 3068 df-reu 3378 df-rab 3433 df-v 3479 df-sbc 3791 df-csb 3908 df-dif 3965 df-un 3967 df-in 3969 df-ss 3979 df-pss 3982 df-nul 4339 df-if 4531 df-pw 4606 df-sn 4631 df-pr 4633 df-op 4637 df-uni 4912 df-int 4951 df-iun 4997 df-br 5148 df-opab 5210 df-mpt 5231 df-tr 5265 df-id 5582 df-eprel 5588 df-po 5596 df-so 5597 df-fr 5640 df-we 5642 df-xp 5694 df-rel 5695 df-cnv 5696 df-co 5697 df-dm 5698 df-rn 5699 df-res 5700 df-ima 5701 df-pred 6322 df-ord 6388 df-on 6389 df-lim 6390 df-suc 6391 df-iota 6515 df-fun 6564 df-fn 6565 df-f 6566 df-f1 6567 df-fo 6568 df-f1o 6569 df-fv 6570 df-ov 7433 df-om 7887 df-2nd 8013 df-frecs 8304 df-wrecs 8335 df-recs 8409 df-rdg 8448 df-r1 9801 df-rank 9802 |
This theorem is referenced by: rankxplim 9916 |
Copyright terms: Public domain | W3C validator |