Metamath Proof Explorer


Theorem ibladdnclem

Description: Lemma for ibladdnc ; cf ibladdlem , whose fifth hypothesis is rendered unnecessary by the weakened hypotheses of itg2addnc . (Contributed by Brendan Leahy, 31-Oct-2017)

Ref Expression
Hypotheses ibladdnclem.1 ⊢ ( ( 𝜑 ∧ 𝑥 ∈ 𝐴 ) → 𝐵 ∈ ℝ )
ibladdnclem.2 ⊢ ( ( 𝜑 ∧ 𝑥 ∈ 𝐴 ) → 𝐶 ∈ ℝ )
ibladdnclem.3 ⊢ ( ( 𝜑 ∧ 𝑥 ∈ 𝐴 ) → 𝐷 = ( 𝐵 + 𝐶 ) )
ibladdnclem.4 ⊢ ( 𝜑 → ( 𝑥 ∈ 𝐴 ↦ 𝐵 ) ∈ MblFn )
ibladdnclem.6 ⊢ ( 𝜑 → ( ∫2 ‘ ( 𝑥 ∈ ℝ ↦ if ( ( 𝑥 ∈ 𝐴 ∧ 0 ≤ 𝐵 ) , 𝐵 , 0 ) ) ) ∈ ℝ )
ibladdnclem.7 ⊢ ( 𝜑 → ( ∫2 ‘ ( 𝑥 ∈ ℝ ↦ if ( ( 𝑥 ∈ 𝐴 ∧ 0 ≤ 𝐶 ) , 𝐶 , 0 ) ) ) ∈ ℝ )
Assertion ibladdnclem ( 𝜑 → ( ∫2 ‘ ( 𝑥 ∈ ℝ ↦ if ( ( 𝑥 ∈ 𝐴 ∧ 0 ≤ 𝐷 ) , 𝐷 , 0 ) ) ) ∈ ℝ )

Proof

Step Hyp Ref Expression
1 ibladdnclem.1 ⊢ ( ( 𝜑 ∧ 𝑥 ∈ 𝐴 ) → 𝐵 ∈ ℝ )
2 ibladdnclem.2 ⊢ ( ( 𝜑 ∧ 𝑥 ∈ 𝐴 ) → 𝐶 ∈ ℝ )
3 ibladdnclem.3 ⊢ ( ( 𝜑 ∧ 𝑥 ∈ 𝐴 ) → 𝐷 = ( 𝐵 + 𝐶 ) )
4 ibladdnclem.4 ⊢ ( 𝜑 → ( 𝑥 ∈ 𝐴 ↦ 𝐵 ) ∈ MblFn )
5 ibladdnclem.6 ⊢ ( 𝜑 → ( ∫2 ‘ ( 𝑥 ∈ ℝ ↦ if ( ( 𝑥 ∈ 𝐴 ∧ 0 ≤ 𝐵 ) , 𝐵 , 0 ) ) ) ∈ ℝ )
6 ibladdnclem.7 ⊢ ( 𝜑 → ( ∫2 ‘ ( 𝑥 ∈ ℝ ↦ if ( ( 𝑥 ∈ 𝐴 ∧ 0 ≤ 𝐶 ) , 𝐶 , 0 ) ) ) ∈ ℝ )
7 ifan ⊢ if ( ( 𝑥 ∈ 𝐴 ∧ 0 ≤ 𝐷 ) , 𝐷 , 0 ) = if ( 𝑥 ∈ 𝐴 , if ( 0 ≤ 𝐷 , 𝐷 , 0 ) , 0 )
8 1 2 readdcld ⊢ ( ( 𝜑 ∧ 𝑥 ∈ 𝐴 ) → ( 𝐵 + 𝐶 ) ∈ ℝ )
9 3 8 eqeltrd ⊢ ( ( 𝜑 ∧ 𝑥 ∈ 𝐴 ) → 𝐷 ∈ ℝ )
10 0re ⊢ 0 ∈ ℝ
11 ifcl ⊢ ( ( 𝐷 ∈ ℝ ∧ 0 ∈ ℝ ) → if ( 0 ≤ 𝐷 , 𝐷 , 0 ) ∈ ℝ )
12 9 10 11 sylancl ⊢ ( ( 𝜑 ∧ 𝑥 ∈ 𝐴 ) → if ( 0 ≤ 𝐷 , 𝐷 , 0 ) ∈ ℝ )
13 12 rexrd ⊢ ( ( 𝜑 ∧ 𝑥 ∈ 𝐴 ) → if ( 0 ≤ 𝐷 , 𝐷 , 0 ) ∈ ℝ* )
14 max1 ⊢ ( ( 0 ∈ ℝ ∧ 𝐷 ∈ ℝ ) → 0 ≤ if ( 0 ≤ 𝐷 , 𝐷 , 0 ) )
15 10 9 14 sylancr ⊢ ( ( 𝜑 ∧ 𝑥 ∈ 𝐴 ) → 0 ≤ if ( 0 ≤ 𝐷 , 𝐷 , 0 ) )
16 elxrge0 ⊢ ( if ( 0 ≤ 𝐷 , 𝐷 , 0 ) ∈ ( 0 [,] +∞ ) ↔ ( if ( 0 ≤ 𝐷 , 𝐷 , 0 ) ∈ ℝ* ∧ 0 ≤ if ( 0 ≤ 𝐷 , 𝐷 , 0 ) ) )
17 13 15 16 sylanbrc ⊢ ( ( 𝜑 ∧ 𝑥 ∈ 𝐴 ) → if ( 0 ≤ 𝐷 , 𝐷 , 0 ) ∈ ( 0 [,] +∞ ) )
18 0e0iccpnf ⊢ 0 ∈ ( 0 [,] +∞ )
19 18 a1i ⊢ ( ( 𝜑 ∧ ¬ 𝑥 ∈ 𝐴 ) → 0 ∈ ( 0 [,] +∞ ) )
20 17 19 ifclda ⊢ ( 𝜑 → if ( 𝑥 ∈ 𝐴 , if ( 0 ≤ 𝐷 , 𝐷 , 0 ) , 0 ) ∈ ( 0 [,] +∞ ) )
21 20 adantr ⊢ ( ( 𝜑 ∧ 𝑥 ∈ ℝ ) → if ( 𝑥 ∈ 𝐴 , if ( 0 ≤ 𝐷 , 𝐷 , 0 ) , 0 ) ∈ ( 0 [,] +∞ ) )
22 7 21 eqeltrid ⊢ ( ( 𝜑 ∧ 𝑥 ∈ ℝ ) → if ( ( 𝑥 ∈ 𝐴 ∧ 0 ≤ 𝐷 ) , 𝐷 , 0 ) ∈ ( 0 [,] +∞ ) )
23 22 fmpttd ⊢ ( 𝜑 → ( 𝑥 ∈ ℝ ↦ if ( ( 𝑥 ∈ 𝐴 ∧ 0 ≤ 𝐷 ) , 𝐷 , 0 ) ) : ℝ ⟶ ( 0 [,] +∞ ) )
24 reex ⊢ ℝ ∈ V
25 24 a1i ⊢ ( 𝜑 → ℝ ∈ V )
26 ifan ⊢ if ( ( 𝑥 ∈ 𝐴 ∧ 0 ≤ 𝐵 ) , 𝐵 , 0 ) = if ( 𝑥 ∈ 𝐴 , if ( 0 ≤ 𝐵 , 𝐵 , 0 ) , 0 )
27 ifcl ⊢ ( ( 𝐵 ∈ ℝ ∧ 0 ∈ ℝ ) → if ( 0 ≤ 𝐵 , 𝐵 , 0 ) ∈ ℝ )
28 1 10 27 sylancl ⊢ ( ( 𝜑 ∧ 𝑥 ∈ 𝐴 ) → if ( 0 ≤ 𝐵 , 𝐵 , 0 ) ∈ ℝ )
29 10 a1i ⊢ ( ( 𝜑 ∧ ¬ 𝑥 ∈ 𝐴 ) → 0 ∈ ℝ )
30 28 29 ifclda ⊢ ( 𝜑 → if ( 𝑥 ∈ 𝐴 , if ( 0 ≤ 𝐵 , 𝐵 , 0 ) , 0 ) ∈ ℝ )
31 26 30 eqeltrid ⊢ ( 𝜑 → if ( ( 𝑥 ∈ 𝐴 ∧ 0 ≤ 𝐵 ) , 𝐵 , 0 ) ∈ ℝ )
32 31 adantr ⊢ ( ( 𝜑 ∧ 𝑥 ∈ ℝ ) → if ( ( 𝑥 ∈ 𝐴 ∧ 0 ≤ 𝐵 ) , 𝐵 , 0 ) ∈ ℝ )
33 ifan ⊢ if ( ( 𝑥 ∈ 𝐴 ∧ 0 ≤ 𝐶 ) , 𝐶 , 0 ) = if ( 𝑥 ∈ 𝐴 , if ( 0 ≤ 𝐶 , 𝐶 , 0 ) , 0 )
34 ifcl ⊢ ( ( 𝐶 ∈ ℝ ∧ 0 ∈ ℝ ) → if ( 0 ≤ 𝐶 , 𝐶 , 0 ) ∈ ℝ )
35 2 10 34 sylancl ⊢ ( ( 𝜑 ∧ 𝑥 ∈ 𝐴 ) → if ( 0 ≤ 𝐶 , 𝐶 , 0 ) ∈ ℝ )
36 35 29 ifclda ⊢ ( 𝜑 → if ( 𝑥 ∈ 𝐴 , if ( 0 ≤ 𝐶 , 𝐶 , 0 ) , 0 ) ∈ ℝ )
37 33 36 eqeltrid ⊢ ( 𝜑 → if ( ( 𝑥 ∈ 𝐴 ∧ 0 ≤ 𝐶 ) , 𝐶 , 0 ) ∈ ℝ )
38 37 adantr ⊢ ( ( 𝜑 ∧ 𝑥 ∈ ℝ ) → if ( ( 𝑥 ∈ 𝐴 ∧ 0 ≤ 𝐶 ) , 𝐶 , 0 ) ∈ ℝ )
39 eqidd ⊢ ( 𝜑 → ( 𝑥 ∈ ℝ ↦ if ( ( 𝑥 ∈ 𝐴 ∧ 0 ≤ 𝐵 ) , 𝐵 , 0 ) ) = ( 𝑥 ∈ ℝ ↦ if ( ( 𝑥 ∈ 𝐴 ∧ 0 ≤ 𝐵 ) , 𝐵 , 0 ) ) )
40 eqidd ⊢ ( 𝜑 → ( 𝑥 ∈ ℝ ↦ if ( ( 𝑥 ∈ 𝐴 ∧ 0 ≤ 𝐶 ) , 𝐶 , 0 ) ) = ( 𝑥 ∈ ℝ ↦ if ( ( 𝑥 ∈ 𝐴 ∧ 0 ≤ 𝐶 ) , 𝐶 , 0 ) ) )
41 25 32 38 39 40 offval2 ⊢ ( 𝜑 → ( ( 𝑥 ∈ ℝ ↦ if ( ( 𝑥 ∈ 𝐴 ∧ 0 ≤ 𝐵 ) , 𝐵 , 0 ) ) ∘f + ( 𝑥 ∈ ℝ ↦ if ( ( 𝑥 ∈ 𝐴 ∧ 0 ≤ 𝐶 ) , 𝐶 , 0 ) ) ) = ( 𝑥 ∈ ℝ ↦ ( if ( ( 𝑥 ∈ 𝐴 ∧ 0 ≤ 𝐵 ) , 𝐵 , 0 ) + if ( ( 𝑥 ∈ 𝐴 ∧ 0 ≤ 𝐶 ) , 𝐶 , 0 ) ) ) )
42 iftrue ⊢ ( 𝑥 ∈ 𝐴 → if ( 𝑥 ∈ 𝐴 , ( if ( 0 ≤ 𝐵 , 𝐵 , 0 ) + if ( 0 ≤ 𝐶 , 𝐶 , 0 ) ) , 0 ) = ( if ( 0 ≤ 𝐵 , 𝐵 , 0 ) + if ( 0 ≤ 𝐶 , 𝐶 , 0 ) ) )
43 ibar ⊢ ( 𝑥 ∈ 𝐴 → ( 0 ≤ 𝐵 ↔ ( 𝑥 ∈ 𝐴 ∧ 0 ≤ 𝐵 ) ) )
44 43 ifbid ⊢ ( 𝑥 ∈ 𝐴 → if ( 0 ≤ 𝐵 , 𝐵 , 0 ) = if ( ( 𝑥 ∈ 𝐴 ∧ 0 ≤ 𝐵 ) , 𝐵 , 0 ) )
45 ibar ⊢ ( 𝑥 ∈ 𝐴 → ( 0 ≤ 𝐶 ↔ ( 𝑥 ∈ 𝐴 ∧ 0 ≤ 𝐶 ) ) )
46 45 ifbid ⊢ ( 𝑥 ∈ 𝐴 → if ( 0 ≤ 𝐶 , 𝐶 , 0 ) = if ( ( 𝑥 ∈ 𝐴 ∧ 0 ≤ 𝐶 ) , 𝐶 , 0 ) )
47 44 46 oveq12d ⊢ ( 𝑥 ∈ 𝐴 → ( if ( 0 ≤ 𝐵 , 𝐵 , 0 ) + if ( 0 ≤ 𝐶 , 𝐶 , 0 ) ) = ( if ( ( 𝑥 ∈ 𝐴 ∧ 0 ≤ 𝐵 ) , 𝐵 , 0 ) + if ( ( 𝑥 ∈ 𝐴 ∧ 0 ≤ 𝐶 ) , 𝐶 , 0 ) ) )
48 42 47 eqtr2d ⊢ ( 𝑥 ∈ 𝐴 → ( if ( ( 𝑥 ∈ 𝐴 ∧ 0 ≤ 𝐵 ) , 𝐵 , 0 ) + if ( ( 𝑥 ∈ 𝐴 ∧ 0 ≤ 𝐶 ) , 𝐶 , 0 ) ) = if ( 𝑥 ∈ 𝐴 , ( if ( 0 ≤ 𝐵 , 𝐵 , 0 ) + if ( 0 ≤ 𝐶 , 𝐶 , 0 ) ) , 0 ) )
49 00id ⊢ ( 0 + 0 ) = 0
50 simpl ⊢ ( ( 𝑥 ∈ 𝐴 ∧ 0 ≤ 𝐵 ) → 𝑥 ∈ 𝐴 )
51 50 con3i ⊢ ( ¬ 𝑥 ∈ 𝐴 → ¬ ( 𝑥 ∈ 𝐴 ∧ 0 ≤ 𝐵 ) )
52 51 iffalsed ⊢ ( ¬ 𝑥 ∈ 𝐴 → if ( ( 𝑥 ∈ 𝐴 ∧ 0 ≤ 𝐵 ) , 𝐵 , 0 ) = 0 )
53 simpl ⊢ ( ( 𝑥 ∈ 𝐴 ∧ 0 ≤ 𝐶 ) → 𝑥 ∈ 𝐴 )
54 53 con3i ⊢ ( ¬ 𝑥 ∈ 𝐴 → ¬ ( 𝑥 ∈ 𝐴 ∧ 0 ≤ 𝐶 ) )
55 54 iffalsed ⊢ ( ¬ 𝑥 ∈ 𝐴 → if ( ( 𝑥 ∈ 𝐴 ∧ 0 ≤ 𝐶 ) , 𝐶 , 0 ) = 0 )
56 52 55 oveq12d ⊢ ( ¬ 𝑥 ∈ 𝐴 → ( if ( ( 𝑥 ∈ 𝐴 ∧ 0 ≤ 𝐵 ) , 𝐵 , 0 ) + if ( ( 𝑥 ∈ 𝐴 ∧ 0 ≤ 𝐶 ) , 𝐶 , 0 ) ) = ( 0 + 0 ) )
57 iffalse ⊢ ( ¬ 𝑥 ∈ 𝐴 → if ( 𝑥 ∈ 𝐴 , ( if ( 0 ≤ 𝐵 , 𝐵 , 0 ) + if ( 0 ≤ 𝐶 , 𝐶 , 0 ) ) , 0 ) = 0 )
58 49 56 57 3eqtr4a ⊢ ( ¬ 𝑥 ∈ 𝐴 → ( if ( ( 𝑥 ∈ 𝐴 ∧ 0 ≤ 𝐵 ) , 𝐵 , 0 ) + if ( ( 𝑥 ∈ 𝐴 ∧ 0 ≤ 𝐶 ) , 𝐶 , 0 ) ) = if ( 𝑥 ∈ 𝐴 , ( if ( 0 ≤ 𝐵 , 𝐵 , 0 ) + if ( 0 ≤ 𝐶 , 𝐶 , 0 ) ) , 0 ) )
59 48 58 pm2.61i ⊢ ( if ( ( 𝑥 ∈ 𝐴 ∧ 0 ≤ 𝐵 ) , 𝐵 , 0 ) + if ( ( 𝑥 ∈ 𝐴 ∧ 0 ≤ 𝐶 ) , 𝐶 , 0 ) ) = if ( 𝑥 ∈ 𝐴 , ( if ( 0 ≤ 𝐵 , 𝐵 , 0 ) + if ( 0 ≤ 𝐶 , 𝐶 , 0 ) ) , 0 )
60 59 mpteq2i ⊢ ( 𝑥 ∈ ℝ ↦ ( if ( ( 𝑥 ∈ 𝐴 ∧ 0 ≤ 𝐵 ) , 𝐵 , 0 ) + if ( ( 𝑥 ∈ 𝐴 ∧ 0 ≤ 𝐶 ) , 𝐶 , 0 ) ) ) = ( 𝑥 ∈ ℝ ↦ if ( 𝑥 ∈ 𝐴 , ( if ( 0 ≤ 𝐵 , 𝐵 , 0 ) + if ( 0 ≤ 𝐶 , 𝐶 , 0 ) ) , 0 ) )
61 41 60 eqtrdi ⊢ ( 𝜑 → ( ( 𝑥 ∈ ℝ ↦ if ( ( 𝑥 ∈ 𝐴 ∧ 0 ≤ 𝐵 ) , 𝐵 , 0 ) ) ∘f + ( 𝑥 ∈ ℝ ↦ if ( ( 𝑥 ∈ 𝐴 ∧ 0 ≤ 𝐶 ) , 𝐶 , 0 ) ) ) = ( 𝑥 ∈ ℝ ↦ if ( 𝑥 ∈ 𝐴 , ( if ( 0 ≤ 𝐵 , 𝐵 , 0 ) + if ( 0 ≤ 𝐶 , 𝐶 , 0 ) ) , 0 ) ) )
62 61 fveq2d ⊢ ( 𝜑 → ( ∫2 ‘ ( ( 𝑥 ∈ ℝ ↦ if ( ( 𝑥 ∈ 𝐴 ∧ 0 ≤ 𝐵 ) , 𝐵 , 0 ) ) ∘f + ( 𝑥 ∈ ℝ ↦ if ( ( 𝑥 ∈ 𝐴 ∧ 0 ≤ 𝐶 ) , 𝐶 , 0 ) ) ) ) = ( ∫2 ‘ ( 𝑥 ∈ ℝ ↦ if ( 𝑥 ∈ 𝐴 , ( if ( 0 ≤ 𝐵 , 𝐵 , 0 ) + if ( 0 ≤ 𝐶 , 𝐶 , 0 ) ) , 0 ) ) ) )
63 4 1 mbfdm2 ⊢ ( 𝜑 → 𝐴 ∈ dom vol )
64 mblss ⊢ ( 𝐴 ∈ dom vol → 𝐴 ⊆ ℝ )
65 63 64 syl ⊢ ( 𝜑 → 𝐴 ⊆ ℝ )
66 rembl ⊢ ℝ ∈ dom vol
67 66 a1i ⊢ ( 𝜑 → ℝ ∈ dom vol )
68 31 adantr ⊢ ( ( 𝜑 ∧ 𝑥 ∈ 𝐴 ) → if ( ( 𝑥 ∈ 𝐴 ∧ 0 ≤ 𝐵 ) , 𝐵 , 0 ) ∈ ℝ )
69 eldifn ⊢ ( 𝑥 ∈ ( ℝ ∖ 𝐴 ) → ¬ 𝑥 ∈ 𝐴 )
70 69 adantl ⊢ ( ( 𝜑 ∧ 𝑥 ∈ ( ℝ ∖ 𝐴 ) ) → ¬ 𝑥 ∈ 𝐴 )
71 70 intnanrd ⊢ ( ( 𝜑 ∧ 𝑥 ∈ ( ℝ ∖ 𝐴 ) ) → ¬ ( 𝑥 ∈ 𝐴 ∧ 0 ≤ 𝐵 ) )
72 71 iffalsed ⊢ ( ( 𝜑 ∧ 𝑥 ∈ ( ℝ ∖ 𝐴 ) ) → if ( ( 𝑥 ∈ 𝐴 ∧ 0 ≤ 𝐵 ) , 𝐵 , 0 ) = 0 )
73 44 mpteq2ia ⊢ ( 𝑥 ∈ 𝐴 ↦ if ( 0 ≤ 𝐵 , 𝐵 , 0 ) ) = ( 𝑥 ∈ 𝐴 ↦ if ( ( 𝑥 ∈ 𝐴 ∧ 0 ≤ 𝐵 ) , 𝐵 , 0 ) )
74 1 4 mbfpos ⊢ ( 𝜑 → ( 𝑥 ∈ 𝐴 ↦ if ( 0 ≤ 𝐵 , 𝐵 , 0 ) ) ∈ MblFn )
75 73 74 eqeltrrid ⊢ ( 𝜑 → ( 𝑥 ∈ 𝐴 ↦ if ( ( 𝑥 ∈ 𝐴 ∧ 0 ≤ 𝐵 ) , 𝐵 , 0 ) ) ∈ MblFn )
76 65 67 68 72 75 mbfss ⊢ ( 𝜑 → ( 𝑥 ∈ ℝ ↦ if ( ( 𝑥 ∈ 𝐴 ∧ 0 ≤ 𝐵 ) , 𝐵 , 0 ) ) ∈ MblFn )
77 max1 ⊢ ( ( 0 ∈ ℝ ∧ 𝐵 ∈ ℝ ) → 0 ≤ if ( 0 ≤ 𝐵 , 𝐵 , 0 ) )
78 10 1 77 sylancr ⊢ ( ( 𝜑 ∧ 𝑥 ∈ 𝐴 ) → 0 ≤ if ( 0 ≤ 𝐵 , 𝐵 , 0 ) )
79 elrege0 ⊢ ( if ( 0 ≤ 𝐵 , 𝐵 , 0 ) ∈ ( 0 [,) +∞ ) ↔ ( if ( 0 ≤ 𝐵 , 𝐵 , 0 ) ∈ ℝ ∧ 0 ≤ if ( 0 ≤ 𝐵 , 𝐵 , 0 ) ) )
80 28 78 79 sylanbrc ⊢ ( ( 𝜑 ∧ 𝑥 ∈ 𝐴 ) → if ( 0 ≤ 𝐵 , 𝐵 , 0 ) ∈ ( 0 [,) +∞ ) )
81 0e0icopnf ⊢ 0 ∈ ( 0 [,) +∞ )
82 81 a1i ⊢ ( ( 𝜑 ∧ ¬ 𝑥 ∈ 𝐴 ) → 0 ∈ ( 0 [,) +∞ ) )
83 80 82 ifclda ⊢ ( 𝜑 → if ( 𝑥 ∈ 𝐴 , if ( 0 ≤ 𝐵 , 𝐵 , 0 ) , 0 ) ∈ ( 0 [,) +∞ ) )
84 26 83 eqeltrid ⊢ ( 𝜑 → if ( ( 𝑥 ∈ 𝐴 ∧ 0 ≤ 𝐵 ) , 𝐵 , 0 ) ∈ ( 0 [,) +∞ ) )
85 84 adantr ⊢ ( ( 𝜑 ∧ 𝑥 ∈ ℝ ) → if ( ( 𝑥 ∈ 𝐴 ∧ 0 ≤ 𝐵 ) , 𝐵 , 0 ) ∈ ( 0 [,) +∞ ) )
86 85 fmpttd ⊢ ( 𝜑 → ( 𝑥 ∈ ℝ ↦ if ( ( 𝑥 ∈ 𝐴 ∧ 0 ≤ 𝐵 ) , 𝐵 , 0 ) ) : ℝ ⟶ ( 0 [,) +∞ ) )
87 max1 ⊢ ( ( 0 ∈ ℝ ∧ 𝐶 ∈ ℝ ) → 0 ≤ if ( 0 ≤ 𝐶 , 𝐶 , 0 ) )
88 10 2 87 sylancr ⊢ ( ( 𝜑 ∧ 𝑥 ∈ 𝐴 ) → 0 ≤ if ( 0 ≤ 𝐶 , 𝐶 , 0 ) )
89 elrege0 ⊢ ( if ( 0 ≤ 𝐶 , 𝐶 , 0 ) ∈ ( 0 [,) +∞ ) ↔ ( if ( 0 ≤ 𝐶 , 𝐶 , 0 ) ∈ ℝ ∧ 0 ≤ if ( 0 ≤ 𝐶 , 𝐶 , 0 ) ) )
90 35 88 89 sylanbrc ⊢ ( ( 𝜑 ∧ 𝑥 ∈ 𝐴 ) → if ( 0 ≤ 𝐶 , 𝐶 , 0 ) ∈ ( 0 [,) +∞ ) )
91 90 82 ifclda ⊢ ( 𝜑 → if ( 𝑥 ∈ 𝐴 , if ( 0 ≤ 𝐶 , 𝐶 , 0 ) , 0 ) ∈ ( 0 [,) +∞ ) )
92 33 91 eqeltrid ⊢ ( 𝜑 → if ( ( 𝑥 ∈ 𝐴 ∧ 0 ≤ 𝐶 ) , 𝐶 , 0 ) ∈ ( 0 [,) +∞ ) )
93 92 adantr ⊢ ( ( 𝜑 ∧ 𝑥 ∈ ℝ ) → if ( ( 𝑥 ∈ 𝐴 ∧ 0 ≤ 𝐶 ) , 𝐶 , 0 ) ∈ ( 0 [,) +∞ ) )
94 93 fmpttd ⊢ ( 𝜑 → ( 𝑥 ∈ ℝ ↦ if ( ( 𝑥 ∈ 𝐴 ∧ 0 ≤ 𝐶 ) , 𝐶 , 0 ) ) : ℝ ⟶ ( 0 [,) +∞ ) )
95 76 86 5 94 6 itg2addnc ⊢ ( 𝜑 → ( ∫2 ‘ ( ( 𝑥 ∈ ℝ ↦ if ( ( 𝑥 ∈ 𝐴 ∧ 0 ≤ 𝐵 ) , 𝐵 , 0 ) ) ∘f + ( 𝑥 ∈ ℝ ↦ if ( ( 𝑥 ∈ 𝐴 ∧ 0 ≤ 𝐶 ) , 𝐶 , 0 ) ) ) ) = ( ( ∫2 ‘ ( 𝑥 ∈ ℝ ↦ if ( ( 𝑥 ∈ 𝐴 ∧ 0 ≤ 𝐵 ) , 𝐵 , 0 ) ) ) + ( ∫2 ‘ ( 𝑥 ∈ ℝ ↦ if ( ( 𝑥 ∈ 𝐴 ∧ 0 ≤ 𝐶 ) , 𝐶 , 0 ) ) ) ) )
96 62 95 eqtr3d ⊢ ( 𝜑 → ( ∫2 ‘ ( 𝑥 ∈ ℝ ↦ if ( 𝑥 ∈ 𝐴 , ( if ( 0 ≤ 𝐵 , 𝐵 , 0 ) + if ( 0 ≤ 𝐶 , 𝐶 , 0 ) ) , 0 ) ) ) = ( ( ∫2 ‘ ( 𝑥 ∈ ℝ ↦ if ( ( 𝑥 ∈ 𝐴 ∧ 0 ≤ 𝐵 ) , 𝐵 , 0 ) ) ) + ( ∫2 ‘ ( 𝑥 ∈ ℝ ↦ if ( ( 𝑥 ∈ 𝐴 ∧ 0 ≤ 𝐶 ) , 𝐶 , 0 ) ) ) ) )
97 5 6 readdcld ⊢ ( 𝜑 → ( ( ∫2 ‘ ( 𝑥 ∈ ℝ ↦ if ( ( 𝑥 ∈ 𝐴 ∧ 0 ≤ 𝐵 ) , 𝐵 , 0 ) ) ) + ( ∫2 ‘ ( 𝑥 ∈ ℝ ↦ if ( ( 𝑥 ∈ 𝐴 ∧ 0 ≤ 𝐶 ) , 𝐶 , 0 ) ) ) ) ∈ ℝ )
98 96 97 eqeltrd ⊢ ( 𝜑 → ( ∫2 ‘ ( 𝑥 ∈ ℝ ↦ if ( 𝑥 ∈ 𝐴 , ( if ( 0 ≤ 𝐵 , 𝐵 , 0 ) + if ( 0 ≤ 𝐶 , 𝐶 , 0 ) ) , 0 ) ) ) ∈ ℝ )
99 28 35 readdcld ⊢ ( ( 𝜑 ∧ 𝑥 ∈ 𝐴 ) → ( if ( 0 ≤ 𝐵 , 𝐵 , 0 ) + if ( 0 ≤ 𝐶 , 𝐶 , 0 ) ) ∈ ℝ )
100 99 rexrd ⊢ ( ( 𝜑 ∧ 𝑥 ∈ 𝐴 ) → ( if ( 0 ≤ 𝐵 , 𝐵 , 0 ) + if ( 0 ≤ 𝐶 , 𝐶 , 0 ) ) ∈ ℝ* )
101 28 35 78 88 addge0d ⊢ ( ( 𝜑 ∧ 𝑥 ∈ 𝐴 ) → 0 ≤ ( if ( 0 ≤ 𝐵 , 𝐵 , 0 ) + if ( 0 ≤ 𝐶 , 𝐶 , 0 ) ) )
102 elxrge0 ⊢ ( ( if ( 0 ≤ 𝐵 , 𝐵 , 0 ) + if ( 0 ≤ 𝐶 , 𝐶 , 0 ) ) ∈ ( 0 [,] +∞ ) ↔ ( ( if ( 0 ≤ 𝐵 , 𝐵 , 0 ) + if ( 0 ≤ 𝐶 , 𝐶 , 0 ) ) ∈ ℝ* ∧ 0 ≤ ( if ( 0 ≤ 𝐵 , 𝐵 , 0 ) + if ( 0 ≤ 𝐶 , 𝐶 , 0 ) ) ) )
103 100 101 102 sylanbrc ⊢ ( ( 𝜑 ∧ 𝑥 ∈ 𝐴 ) → ( if ( 0 ≤ 𝐵 , 𝐵 , 0 ) + if ( 0 ≤ 𝐶 , 𝐶 , 0 ) ) ∈ ( 0 [,] +∞ ) )
104 103 19 ifclda ⊢ ( 𝜑 → if ( 𝑥 ∈ 𝐴 , ( if ( 0 ≤ 𝐵 , 𝐵 , 0 ) + if ( 0 ≤ 𝐶 , 𝐶 , 0 ) ) , 0 ) ∈ ( 0 [,] +∞ ) )
105 104 adantr ⊢ ( ( 𝜑 ∧ 𝑥 ∈ ℝ ) → if ( 𝑥 ∈ 𝐴 , ( if ( 0 ≤ 𝐵 , 𝐵 , 0 ) + if ( 0 ≤ 𝐶 , 𝐶 , 0 ) ) , 0 ) ∈ ( 0 [,] +∞ ) )
106 105 fmpttd ⊢ ( 𝜑 → ( 𝑥 ∈ ℝ ↦ if ( 𝑥 ∈ 𝐴 , ( if ( 0 ≤ 𝐵 , 𝐵 , 0 ) + if ( 0 ≤ 𝐶 , 𝐶 , 0 ) ) , 0 ) ) : ℝ ⟶ ( 0 [,] +∞ ) )
107 max2 ⊢ ( ( 0 ∈ ℝ ∧ 𝐵 ∈ ℝ ) → 𝐵 ≤ if ( 0 ≤ 𝐵 , 𝐵 , 0 ) )
108 10 1 107 sylancr ⊢ ( ( 𝜑 ∧ 𝑥 ∈ 𝐴 ) → 𝐵 ≤ if ( 0 ≤ 𝐵 , 𝐵 , 0 ) )
109 max2 ⊢ ( ( 0 ∈ ℝ ∧ 𝐶 ∈ ℝ ) → 𝐶 ≤ if ( 0 ≤ 𝐶 , 𝐶 , 0 ) )
110 10 2 109 sylancr ⊢ ( ( 𝜑 ∧ 𝑥 ∈ 𝐴 ) → 𝐶 ≤ if ( 0 ≤ 𝐶 , 𝐶 , 0 ) )
111 1 2 28 35 108 110 le2addd ⊢ ( ( 𝜑 ∧ 𝑥 ∈ 𝐴 ) → ( 𝐵 + 𝐶 ) ≤ ( if ( 0 ≤ 𝐵 , 𝐵 , 0 ) + if ( 0 ≤ 𝐶 , 𝐶 , 0 ) ) )
112 3 111 eqbrtrd ⊢ ( ( 𝜑 ∧ 𝑥 ∈ 𝐴 ) → 𝐷 ≤ ( if ( 0 ≤ 𝐵 , 𝐵 , 0 ) + if ( 0 ≤ 𝐶 , 𝐶 , 0 ) ) )
113 breq1 ⊢ ( 𝐷 = if ( 0 ≤ 𝐷 , 𝐷 , 0 ) → ( 𝐷 ≤ ( if ( 0 ≤ 𝐵 , 𝐵 , 0 ) + if ( 0 ≤ 𝐶 , 𝐶 , 0 ) ) ↔ if ( 0 ≤ 𝐷 , 𝐷 , 0 ) ≤ ( if ( 0 ≤ 𝐵 , 𝐵 , 0 ) + if ( 0 ≤ 𝐶 , 𝐶 , 0 ) ) ) )
114 breq1 ⊢ ( 0 = if ( 0 ≤ 𝐷 , 𝐷 , 0 ) → ( 0 ≤ ( if ( 0 ≤ 𝐵 , 𝐵 , 0 ) + if ( 0 ≤ 𝐶 , 𝐶 , 0 ) ) ↔ if ( 0 ≤ 𝐷 , 𝐷 , 0 ) ≤ ( if ( 0 ≤ 𝐵 , 𝐵 , 0 ) + if ( 0 ≤ 𝐶 , 𝐶 , 0 ) ) ) )
115 113 114 ifboth ⊢ ( ( 𝐷 ≤ ( if ( 0 ≤ 𝐵 , 𝐵 , 0 ) + if ( 0 ≤ 𝐶 , 𝐶 , 0 ) ) ∧ 0 ≤ ( if ( 0 ≤ 𝐵 , 𝐵 , 0 ) + if ( 0 ≤ 𝐶 , 𝐶 , 0 ) ) ) → if ( 0 ≤ 𝐷 , 𝐷 , 0 ) ≤ ( if ( 0 ≤ 𝐵 , 𝐵 , 0 ) + if ( 0 ≤ 𝐶 , 𝐶 , 0 ) ) )
116 112 101 115 syl2anc ⊢ ( ( 𝜑 ∧ 𝑥 ∈ 𝐴 ) → if ( 0 ≤ 𝐷 , 𝐷 , 0 ) ≤ ( if ( 0 ≤ 𝐵 , 𝐵 , 0 ) + if ( 0 ≤ 𝐶 , 𝐶 , 0 ) ) )
117 iftrue ⊢ ( 𝑥 ∈ 𝐴 → if ( 𝑥 ∈ 𝐴 , if ( 0 ≤ 𝐷 , 𝐷 , 0 ) , 0 ) = if ( 0 ≤ 𝐷 , 𝐷 , 0 ) )
118 117 adantl ⊢ ( ( 𝜑 ∧ 𝑥 ∈ 𝐴 ) → if ( 𝑥 ∈ 𝐴 , if ( 0 ≤ 𝐷 , 𝐷 , 0 ) , 0 ) = if ( 0 ≤ 𝐷 , 𝐷 , 0 ) )
119 42 adantl ⊢ ( ( 𝜑 ∧ 𝑥 ∈ 𝐴 ) → if ( 𝑥 ∈ 𝐴 , ( if ( 0 ≤ 𝐵 , 𝐵 , 0 ) + if ( 0 ≤ 𝐶 , 𝐶 , 0 ) ) , 0 ) = ( if ( 0 ≤ 𝐵 , 𝐵 , 0 ) + if ( 0 ≤ 𝐶 , 𝐶 , 0 ) ) )
120 116 118 119 3brtr4d ⊢ ( ( 𝜑 ∧ 𝑥 ∈ 𝐴 ) → if ( 𝑥 ∈ 𝐴 , if ( 0 ≤ 𝐷 , 𝐷 , 0 ) , 0 ) ≤ if ( 𝑥 ∈ 𝐴 , ( if ( 0 ≤ 𝐵 , 𝐵 , 0 ) + if ( 0 ≤ 𝐶 , 𝐶 , 0 ) ) , 0 ) )
121 120 ex ⊢ ( 𝜑 → ( 𝑥 ∈ 𝐴 → if ( 𝑥 ∈ 𝐴 , if ( 0 ≤ 𝐷 , 𝐷 , 0 ) , 0 ) ≤ if ( 𝑥 ∈ 𝐴 , ( if ( 0 ≤ 𝐵 , 𝐵 , 0 ) + if ( 0 ≤ 𝐶 , 𝐶 , 0 ) ) , 0 ) ) )
122 0le0 ⊢ 0 ≤ 0
123 122 a1i ⊢ ( ¬ 𝑥 ∈ 𝐴 → 0 ≤ 0 )
124 iffalse ⊢ ( ¬ 𝑥 ∈ 𝐴 → if ( 𝑥 ∈ 𝐴 , if ( 0 ≤ 𝐷 , 𝐷 , 0 ) , 0 ) = 0 )
125 123 124 57 3brtr4d ⊢ ( ¬ 𝑥 ∈ 𝐴 → if ( 𝑥 ∈ 𝐴 , if ( 0 ≤ 𝐷 , 𝐷 , 0 ) , 0 ) ≤ if ( 𝑥 ∈ 𝐴 , ( if ( 0 ≤ 𝐵 , 𝐵 , 0 ) + if ( 0 ≤ 𝐶 , 𝐶 , 0 ) ) , 0 ) )
126 121 125 pm2.61d1 ⊢ ( 𝜑 → if ( 𝑥 ∈ 𝐴 , if ( 0 ≤ 𝐷 , 𝐷 , 0 ) , 0 ) ≤ if ( 𝑥 ∈ 𝐴 , ( if ( 0 ≤ 𝐵 , 𝐵 , 0 ) + if ( 0 ≤ 𝐶 , 𝐶 , 0 ) ) , 0 ) )
127 7 126 eqbrtrid ⊢ ( 𝜑 → if ( ( 𝑥 ∈ 𝐴 ∧ 0 ≤ 𝐷 ) , 𝐷 , 0 ) ≤ if ( 𝑥 ∈ 𝐴 , ( if ( 0 ≤ 𝐵 , 𝐵 , 0 ) + if ( 0 ≤ 𝐶 , 𝐶 , 0 ) ) , 0 ) )
128 127 ralrimivw ⊢ ( 𝜑 → ∀ 𝑥 ∈ ℝ if ( ( 𝑥 ∈ 𝐴 ∧ 0 ≤ 𝐷 ) , 𝐷 , 0 ) ≤ if ( 𝑥 ∈ 𝐴 , ( if ( 0 ≤ 𝐵 , 𝐵 , 0 ) + if ( 0 ≤ 𝐶 , 𝐶 , 0 ) ) , 0 ) )
129 eqidd ⊢ ( 𝜑 → ( 𝑥 ∈ ℝ ↦ if ( ( 𝑥 ∈ 𝐴 ∧ 0 ≤ 𝐷 ) , 𝐷 , 0 ) ) = ( 𝑥 ∈ ℝ ↦ if ( ( 𝑥 ∈ 𝐴 ∧ 0 ≤ 𝐷 ) , 𝐷 , 0 ) ) )
130 eqidd ⊢ ( 𝜑 → ( 𝑥 ∈ ℝ ↦ if ( 𝑥 ∈ 𝐴 , ( if ( 0 ≤ 𝐵 , 𝐵 , 0 ) + if ( 0 ≤ 𝐶 , 𝐶 , 0 ) ) , 0 ) ) = ( 𝑥 ∈ ℝ ↦ if ( 𝑥 ∈ 𝐴 , ( if ( 0 ≤ 𝐵 , 𝐵 , 0 ) + if ( 0 ≤ 𝐶 , 𝐶 , 0 ) ) , 0 ) ) )
131 25 22 105 129 130 ofrfval2 ⊢ ( 𝜑 → ( ( 𝑥 ∈ ℝ ↦ if ( ( 𝑥 ∈ 𝐴 ∧ 0 ≤ 𝐷 ) , 𝐷 , 0 ) ) ∘r ≤ ( 𝑥 ∈ ℝ ↦ if ( 𝑥 ∈ 𝐴 , ( if ( 0 ≤ 𝐵 , 𝐵 , 0 ) + if ( 0 ≤ 𝐶 , 𝐶 , 0 ) ) , 0 ) ) ↔ ∀ 𝑥 ∈ ℝ if ( ( 𝑥 ∈ 𝐴 ∧ 0 ≤ 𝐷 ) , 𝐷 , 0 ) ≤ if ( 𝑥 ∈ 𝐴 , ( if ( 0 ≤ 𝐵 , 𝐵 , 0 ) + if ( 0 ≤ 𝐶 , 𝐶 , 0 ) ) , 0 ) ) )
132 128 131 mpbird ⊢ ( 𝜑 → ( 𝑥 ∈ ℝ ↦ if ( ( 𝑥 ∈ 𝐴 ∧ 0 ≤ 𝐷 ) , 𝐷 , 0 ) ) ∘r ≤ ( 𝑥 ∈ ℝ ↦ if ( 𝑥 ∈ 𝐴 , ( if ( 0 ≤ 𝐵 , 𝐵 , 0 ) + if ( 0 ≤ 𝐶 , 𝐶 , 0 ) ) , 0 ) ) )
133 itg2le ⊢ ( ( ( 𝑥 ∈ ℝ ↦ if ( ( 𝑥 ∈ 𝐴 ∧ 0 ≤ 𝐷 ) , 𝐷 , 0 ) ) : ℝ ⟶ ( 0 [,] +∞ ) ∧ ( 𝑥 ∈ ℝ ↦ if ( 𝑥 ∈ 𝐴 , ( if ( 0 ≤ 𝐵 , 𝐵 , 0 ) + if ( 0 ≤ 𝐶 , 𝐶 , 0 ) ) , 0 ) ) : ℝ ⟶ ( 0 [,] +∞ ) ∧ ( 𝑥 ∈ ℝ ↦ if ( ( 𝑥 ∈ 𝐴 ∧ 0 ≤ 𝐷 ) , 𝐷 , 0 ) ) ∘r ≤ ( 𝑥 ∈ ℝ ↦ if ( 𝑥 ∈ 𝐴 , ( if ( 0 ≤ 𝐵 , 𝐵 , 0 ) + if ( 0 ≤ 𝐶 , 𝐶 , 0 ) ) , 0 ) ) ) → ( ∫2 ‘ ( 𝑥 ∈ ℝ ↦ if ( ( 𝑥 ∈ 𝐴 ∧ 0 ≤ 𝐷 ) , 𝐷 , 0 ) ) ) ≤ ( ∫2 ‘ ( 𝑥 ∈ ℝ ↦ if ( 𝑥 ∈ 𝐴 , ( if ( 0 ≤ 𝐵 , 𝐵 , 0 ) + if ( 0 ≤ 𝐶 , 𝐶 , 0 ) ) , 0 ) ) ) )
134 23 106 132 133 syl3anc ⊢ ( 𝜑 → ( ∫2 ‘ ( 𝑥 ∈ ℝ ↦ if ( ( 𝑥 ∈ 𝐴 ∧ 0 ≤ 𝐷 ) , 𝐷 , 0 ) ) ) ≤ ( ∫2 ‘ ( 𝑥 ∈ ℝ ↦ if ( 𝑥 ∈ 𝐴 , ( if ( 0 ≤ 𝐵 , 𝐵 , 0 ) + if ( 0 ≤ 𝐶 , 𝐶 , 0 ) ) , 0 ) ) ) )
135 itg2lecl ⊢ ( ( ( 𝑥 ∈ ℝ ↦ if ( ( 𝑥 ∈ 𝐴 ∧ 0 ≤ 𝐷 ) , 𝐷 , 0 ) ) : ℝ ⟶ ( 0 [,] +∞ ) ∧ ( ∫2 ‘ ( 𝑥 ∈ ℝ ↦ if ( 𝑥 ∈ 𝐴 , ( if ( 0 ≤ 𝐵 , 𝐵 , 0 ) + if ( 0 ≤ 𝐶 , 𝐶 , 0 ) ) , 0 ) ) ) ∈ ℝ ∧ ( ∫2 ‘ ( 𝑥 ∈ ℝ ↦ if ( ( 𝑥 ∈ 𝐴 ∧ 0 ≤ 𝐷 ) , 𝐷 , 0 ) ) ) ≤ ( ∫2 ‘ ( 𝑥 ∈ ℝ ↦ if ( 𝑥 ∈ 𝐴 , ( if ( 0 ≤ 𝐵 , 𝐵 , 0 ) + if ( 0 ≤ 𝐶 , 𝐶 , 0 ) ) , 0 ) ) ) ) → ( ∫2 ‘ ( 𝑥 ∈ ℝ ↦ if ( ( 𝑥 ∈ 𝐴 ∧ 0 ≤ 𝐷 ) , 𝐷 , 0 ) ) ) ∈ ℝ )
136 23 98 134 135 syl3anc ⊢ ( 𝜑 → ( ∫2 ‘ ( 𝑥 ∈ ℝ ↦ if ( ( 𝑥 ∈ 𝐴 ∧ 0 ≤ 𝐷 ) , 𝐷 , 0 ) ) ) ∈ ℝ )