Theorem itgex 25723

Description: An integral is a set. (Contributed by Mario Carneiro, 28-Jun-2014.)

Assertion

Ref	Expression
itgex	⊢ ∫𝐴𝐵 d𝑥 ∈ V

Proof of Theorem itgex

Dummy variables 𝑘 𝑦 are mutually distinct and distinct from all other variables.

Step	Hyp	Ref	Expression
1		df-itg 25576	. 2 ⊢ ∫𝐴𝐵 d𝑥 = Σ𝑘 ∈ (0...3)((i↑𝑘) · (∫2‘(𝑥 ∈ ℝ ↦ ⦋(ℜ‘(𝐵 / (i↑𝑘))) / 𝑦⦌if((𝑥 ∈ 𝐴 ∧ 0 ≤ 𝑦), 𝑦, 0))))
2		sumex 15704	. 2 ⊢ Σ𝑘 ∈ (0...3)((i↑𝑘) · (∫2‘(𝑥 ∈ ℝ ↦ ⦋(ℜ‘(𝐵 / (i↑𝑘))) / 𝑦⦌if((𝑥 ∈ 𝐴 ∧ 0 ≤ 𝑦), 𝑦, 0)))) ∈ V
3	1, 2	eqeltri 2830	1 ⊢ ∫𝐴𝐵 d𝑥 ∈ V

Syntax hints:   ∧ wa 395   ∈ wcel 2108  Vcvv 3459  ⦋csb 3874  ifcif 4500   class class class wbr 5119   ↦ cmpt 5201  ‘cfv 6531  (class class class)co 7405  ℝcr 11128  0cc0 11129  ici 11131   · cmul 11134   ≤ cle 11270   / cdiv 11894  3c3 12296  ...cfz 13524  ↑cexp 14079  ℜcre 15116  Σcsu 15702  ∫₂citg2 25569  ∫citg 25571

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1795  ax-4 1809  ax-5 1910  ax-6 1967  ax-7 2007  ax-8 2110  ax-9 2118  ax-ext 2707  ax-nul 5276

This theorem depends on definitions:  df-bi 207  df-an 396  df-or 848  df-tru 1543  df-fal 1553  df-ex 1780  df-sb 2065  df-clab 2714  df-cleq 2727  df-clel 2809  df-ne 2933  df-v 3461  df-dif 3929  df-un 3931  df-ss 3943  df-nul 4309  df-sn 4602  df-pr 4604  df-uni 4884  df-iota 6484  df-sum 15703  df-itg 25576

This theorem is referenced by:  ditgex  25805  ftc1lem1  25994  itgulm  26369  dmarea  26919  dfarea  26922  areaval  26926  ftc1anc  37725  itgsinexp  45984  wallispilem1  46094  wallispilem2  46095