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Theorem disjnims 3889
 Description: If a collection 𝐵(𝑖) for 𝑖 ∈ 𝐴 is disjoint, then pairs are disjoint. (Contributed by Mario Carneiro, 14-Nov-2016.) (Revised by Jim Kingdon, 7-Oct-2022.)
Assertion
Ref Expression
disjnims (Disj 𝑥𝐴 𝐵 → ∀𝑖𝐴𝑗𝐴 (𝑖𝑗 → (𝑖 / 𝑥𝐵𝑗 / 𝑥𝐵) = ∅))
Distinct variable groups:   𝑖,𝑗,𝑥,𝐴   𝐵,𝑖,𝑗
Allowed substitution hint:   𝐵(𝑥)

Proof of Theorem disjnims
StepHypRef Expression
1 nfcv 2256 . . 3 𝑖𝐵
2 nfcsb1v 3003 . . 3 𝑥𝑖 / 𝑥𝐵
3 csbeq1a 2981 . . 3 (𝑥 = 𝑖𝐵 = 𝑖 / 𝑥𝐵)
41, 2, 3cbvdisj 3884 . 2 (Disj 𝑥𝐴 𝐵Disj 𝑖𝐴 𝑖 / 𝑥𝐵)
5 csbeq1 2976 . . 3 (𝑖 = 𝑗𝑖 / 𝑥𝐵 = 𝑗 / 𝑥𝐵)
65disjnim 3888 . 2 (Disj 𝑖𝐴 𝑖 / 𝑥𝐵 → ∀𝑖𝐴𝑗𝐴 (𝑖𝑗 → (𝑖 / 𝑥𝐵𝑗 / 𝑥𝐵) = ∅))
74, 6sylbi 120 1 (Disj 𝑥𝐴 𝐵 → ∀𝑖𝐴𝑗𝐴 (𝑖𝑗 → (𝑖 / 𝑥𝐵𝑗 / 𝑥𝐵) = ∅))
 Colors of variables: wff set class Syntax hints:   → wi 4   = wceq 1314   ≠ wne 2283  ∀wral 2391  ⦋csb 2973   ∩ cin 3038  ∅c0 3331  Disj wdisj 3874 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 586  ax-in2 587  ax-io 681  ax-5 1406  ax-7 1407  ax-gen 1408  ax-ie1 1452  ax-ie2 1453  ax-8 1465  ax-10 1466  ax-11 1467  ax-i12 1468  ax-bndl 1469  ax-4 1470  ax-17 1489  ax-i9 1493  ax-ial 1497  ax-i5r 1498  ax-ext 2097 This theorem depends on definitions:  df-bi 116  df-tru 1317  df-fal 1320  df-nf 1420  df-sb 1719  df-eu 1978  df-mo 1979  df-clab 2102  df-cleq 2108  df-clel 2111  df-nfc 2245  df-ne 2284  df-ral 2396  df-rex 2397  df-reu 2398  df-rmo 2399  df-v 2660  df-sbc 2881  df-csb 2974  df-dif 3041  df-in 3045  df-nul 3332  df-disj 3875 This theorem is referenced by:  disji2  3890
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