Theorem cnmpt2c 23902

Description: A constant function is continuous. (Contributed by Mario Carneiro, 5-May-2014.) (Revised by Mario Carneiro, 22-Aug-2015.)

Hypotheses

Ref	Expression
cnmpt21.j	⊢ (𝜑 → 𝐽 ∈ (TopOn‘𝑋))
cnmpt21.k	⊢ (𝜑 → 𝐾 ∈ (TopOn‘𝑌))
cnmpt2c.l	⊢ (𝜑 → 𝐿 ∈ (TopOn‘𝑍))
cnmpt2c.p	⊢ (𝜑 → 𝑃 ∈ 𝑍)

Assertion

Ref	Expression
cnmpt2c	⊢ (𝜑 → (𝑥 ∈ 𝑋, 𝑦 ∈ 𝑌 ↦ 𝑃) ∈ ((𝐽 ×t 𝐾) Cn 𝐿))

Distinct variable groups:   𝑥,𝑦,𝐿   𝜑,𝑥,𝑦   𝑥,𝑋,𝑦   𝑥,𝑃,𝑦   𝑥,𝑌,𝑦   𝑥,𝑍,𝑦

Allowed substitution hints:   𝐽(𝑥, 𝑦)   𝐾(𝑥, 𝑦)

Proof of Theorem cnmpt2c

Dummy variable 𝑧 is distinct from all other variables.

Step	Hyp	Ref	Expression
1		eqidd 2763	. . 3 ⊢ (𝑧 = ⟨𝑥, 𝑦⟩ → 𝑃 = 𝑃)
2	1	mpompt 7531	. 2 ⊢ (𝑧 ∈ (𝑋 × 𝑌) ↦ 𝑃) = (𝑥 ∈ 𝑋, 𝑦 ∈ 𝑌 ↦ 𝑃)
3		cnmpt21.j	. . . 4 ⊢ (𝜑 → 𝐽 ∈ (TopOn‘𝑋))
4		cnmpt21.k	. . . 4 ⊢ (𝜑 → 𝐾 ∈ (TopOn‘𝑌))
5		txtopon 23823	. . . 4 ⊢ ((𝐽 ∈ (TopOn‘𝑋) ∧ 𝐾 ∈ (TopOn‘𝑌)) → (𝐽 ×t 𝐾) ∈ (TopOn‘(𝑋 × 𝑌)))
6	3, 4, 5	syl2anc 596	. . 3 ⊢ (𝜑 → (𝐽 ×t 𝐾) ∈ (TopOn‘(𝑋 × 𝑌)))
7		cnmpt2c.l	. . 3 ⊢ (𝜑 → 𝐿 ∈ (TopOn‘𝑍))
8		cnmpt2c.p	. . 3 ⊢ (𝜑 → 𝑃 ∈ 𝑍)
9	6, 7, 8	cnmptc 23894	. 2 ⊢ (𝜑 → (𝑧 ∈ (𝑋 × 𝑌) ↦ 𝑃) ∈ ((𝐽 ×t 𝐾) Cn 𝐿))
10	2, 9	eqeltrrid 2867	1 ⊢ (𝜑 → (𝑥 ∈ 𝑋, 𝑦 ∈ 𝑌 ↦ 𝑃) ∈ ((𝐽 ×t 𝐾) Cn 𝐿))

This proof depends on syntax axioms:   → wi 4   = wceq 1570   ∈ wcel 2145  ⟨cop 4593   ↦ cmpt 5190   × cxp 5657  ‘cfv 6537  (class class class)co 7417   ∈ cmpo 7419  TopOnctopon 23141   Cn ccn 23455   ×_t ctx 23792

This proof depends on axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1828  ax-4 1842  ax-5 1943  ax-6 2000  ax-7 2041  ax-8 2147  ax-9 2155  ax-10 2178  ax-11 2194  ax-12 2215  ax-ext 2734  ax-sep 5255  ax-nul 5267  ax-pow 5334  ax-pr 5402  ax-un 7740

This proof depends on definitions:  df-bi 210  df-an 402  df-or 862  df-3an 1105  df-tru 1573  df-fal 1583  df-ex 1813  df-nf 1817  df-sb 2100  df-mo 2566  df-eu 2596  df-clab 2741  df-cleq 2754  df-clel 2837  df-nfc 2911  df-ne 2958  df-ral 3079  df-rex 3089  df-rab 3415  df-v 3455  df-sbc 3743  df-csb 3851  df-dif 3905  df-un 3907  df-in 3909  df-ss 3919  df-nul 4283  df-if 4486  df-pw 4562  df-sn 4588  df-pr 4590  df-op 4594  df-uni 4871  df-iun 4956  df-br 5108  df-opab 5172  df-mpt 5191  df-id 5554  df-xp 5665  df-rel 5666  df-cnv 5667  df-co 5668  df-dm 5669  df-rn 5670  df-res 5671  df-ima 5672  df-iota 6493  df-fun 6539  df-fn 6540  df-f 6541  df-fv 6545  df-ov 7420  df-oprab 7421  df-mpo 7422  df-1st 7990  df-2nd 7991  df-map 8832  df-topgen 17534  df-top 23125  df-topon 23142  df-bases 23177  df-cn 23458  df-cnp 23459  df-tx 23794

This theorem is used by:  cnrehmeo  25187  pcopt  25256  pcopt2  25257  vmcn  31188  dipcn  31209  cvxsconn  35830