Theorem ssxp1 5057

Description: Cross product subset cancellation. (Contributed by Jim Kingdon, 14-Dec-2018.)

Assertion

Ref	Expression
ssxp1	⊢ (∃𝑥 𝑥 ∈ 𝐶 → ((𝐴 × 𝐶) ⊆ (𝐵 × 𝐶) ↔ 𝐴 ⊆ 𝐵))

Distinct variable group:   𝑥,𝐶

Allowed substitution hints:   𝐴(𝑥)   𝐵(𝑥)

Proof of Theorem ssxp1

Step	Hyp	Ref	Expression
1		dmxpm 4840	. . . . . 6 ⊢ (∃𝑥 𝑥 ∈ 𝐶 → dom (𝐴 × 𝐶) = 𝐴)
2	1	adantr 276	. . . . 5 ⊢ ((∃𝑥 𝑥 ∈ 𝐶 ∧ (𝐴 × 𝐶) ⊆ (𝐵 × 𝐶)) → dom (𝐴 × 𝐶) = 𝐴)
3		dmss 4819	. . . . . 6 ⊢ ((𝐴 × 𝐶) ⊆ (𝐵 × 𝐶) → dom (𝐴 × 𝐶) ⊆ dom (𝐵 × 𝐶))
4	3	adantl 277	. . . . 5 ⊢ ((∃𝑥 𝑥 ∈ 𝐶 ∧ (𝐴 × 𝐶) ⊆ (𝐵 × 𝐶)) → dom (𝐴 × 𝐶) ⊆ dom (𝐵 × 𝐶))
5	2, 4	eqsstrrd 3190	. . . 4 ⊢ ((∃𝑥 𝑥 ∈ 𝐶 ∧ (𝐴 × 𝐶) ⊆ (𝐵 × 𝐶)) → 𝐴 ⊆ dom (𝐵 × 𝐶))
6		dmxpss 5051	. . . 4 ⊢ dom (𝐵 × 𝐶) ⊆ 𝐵
7	5, 6	sstrdi 3165	. . 3 ⊢ ((∃𝑥 𝑥 ∈ 𝐶 ∧ (𝐴 × 𝐶) ⊆ (𝐵 × 𝐶)) → 𝐴 ⊆ 𝐵)
8	7	ex 115	. 2 ⊢ (∃𝑥 𝑥 ∈ 𝐶 → ((𝐴 × 𝐶) ⊆ (𝐵 × 𝐶) → 𝐴 ⊆ 𝐵))
9		xpss1 4730	. 2 ⊢ (𝐴 ⊆ 𝐵 → (𝐴 × 𝐶) ⊆ (𝐵 × 𝐶))
10	8, 9	impbid1 142	1 ⊢ (∃𝑥 𝑥 ∈ 𝐶 → ((𝐴 × 𝐶) ⊆ (𝐵 × 𝐶) ↔ 𝐴 ⊆ 𝐵))

Syntax hints:   → wi 4   ∧ wa 104   ↔ wb 105   = wceq 1353  ∃wex 1490   ∈ wcel 2146   ⊆ wss 3127   × cxp 4618  dom cdm 4620

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 106  ax-ia2 107  ax-ia3 108  ax-io 709  ax-5 1445  ax-7 1446  ax-gen 1447  ax-ie1 1491  ax-ie2 1492  ax-8 1502  ax-10 1503  ax-11 1504  ax-i12 1505  ax-bndl 1507  ax-4 1508  ax-17 1524  ax-i9 1528  ax-ial 1532  ax-i5r 1533  ax-14 2149  ax-ext 2157  ax-sep 4116  ax-pow 4169  ax-pr 4203

This theorem depends on definitions:  df-bi 117  df-3an 980  df-tru 1356  df-nf 1459  df-sb 1761  df-eu 2027  df-mo 2028  df-clab 2162  df-cleq 2168  df-clel 2171  df-nfc 2306  df-ral 2458  df-rex 2459  df-v 2737  df-un 3131  df-in 3133  df-ss 3140  df-pw 3574  df-sn 3595  df-pr 3596  df-op 3598  df-br 3999  df-opab 4060  df-xp 4626  df-dm 4630

This theorem is referenced by:  xpcan2m  5061