Theorem meacl 46473

Description: The measure of a set is a nonnegative extended real. (Contributed by Glauco Siliprandi, 17-Aug-2020.)

Hypotheses

Ref	Expression
meacl.1	⊢ (𝜑 → 𝑀 ∈ Meas)
meacl.2	⊢ 𝑆 = dom 𝑀
meacl.3	⊢ (𝜑 → 𝐴 ∈ 𝑆)

Assertion

Ref	Expression
meacl	⊢ (𝜑 → (𝑀‘𝐴) ∈ (0[,]+∞))

Proof of Theorem meacl

Step	Hyp	Ref	Expression
1		meacl.1	. . 3 ⊢ (𝜑 → 𝑀 ∈ Meas)
2		meacl.2	. . 3 ⊢ 𝑆 = dom 𝑀
3	1, 2	meaf 46468	. 2 ⊢ (𝜑 → 𝑀:𝑆⟶(0[,]+∞))
4		meacl.3	. 2 ⊢ (𝜑 → 𝐴 ∈ 𝑆)
5	3, 4	ffvelcdmd 7105	1 ⊢ (𝜑 → (𝑀‘𝐴) ∈ (0[,]+∞))

Syntax hints:   → wi 4   = wceq 1540   ∈ wcel 2108  dom cdm 5685  ‘cfv 6561  (class class class)co 7431  0cc0 11155  +∞cpnf 11292  [,]cicc 13390  Meascmea 46464

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-10 2141  ax-11 2157  ax-12 2177  ax-ext 2708  ax-rep 5279  ax-sep 5296  ax-nul 5306  ax-pr 5432

This theorem depends on definitions:  df-bi 207  df-an 396  df-or 849  df-3an 1089  df-tru 1543  df-fal 1553  df-ex 1780  df-nf 1784  df-sb 2065  df-mo 2540  df-eu 2569  df-clab 2715  df-cleq 2729  df-clel 2816  df-nfc 2892  df-ne 2941  df-ral 3062  df-rex 3071  df-reu 3381  df-rab 3437  df-v 3482  df-sbc 3789  df-csb 3900  df-dif 3954  df-un 3956  df-in 3958  df-ss 3968  df-nul 4334  df-if 4526  df-pw 4602  df-sn 4627  df-pr 4629  df-op 4633  df-uni 4908  df-iun 4993  df-br 5144  df-opab 5206  df-mpt 5226  df-id 5578  df-xp 5691  df-rel 5692  df-cnv 5693  df-co 5694  df-dm 5695  df-rn 5696  df-res 5697  df-ima 5698  df-iota 6514  df-fun 6563  df-fn 6564  df-f 6565  df-f1 6566  df-fo 6567  df-f1o 6568  df-fv 6569  df-mea 46465

This theorem is referenced by:  meaxrcl  46476  meassle  46478  meaiunlelem  46483  meage0  46490  voncl  46681