Metamath Proof Explorer


Theorem itgaddnc

Description: Choice-free analogue of itgadd . (Contributed by Brendan Leahy, 11-Nov-2017)

Ref Expression
Hypotheses ibladdnc.1 φ x A B V
ibladdnc.2 φ x A B 𝐿 1
ibladdnc.3 φ x A C V
ibladdnc.4 φ x A C 𝐿 1
ibladdnc.m φ x A B + C MblFn
Assertion itgaddnc φ A B + C dx = A B dx + A C dx

Proof

Step Hyp Ref Expression
1 ibladdnc.1 φ x A B V
2 ibladdnc.2 φ x A B 𝐿 1
3 ibladdnc.3 φ x A C V
4 ibladdnc.4 φ x A C 𝐿 1
5 ibladdnc.m φ x A B + C MblFn
6 iblmbf x A B 𝐿 1 x A B MblFn
7 2 6 syl φ x A B MblFn
8 7 1 mbfmptcl φ x A B
9 iblmbf x A C 𝐿 1 x A C MblFn
10 4 9 syl φ x A C MblFn
11 10 3 mbfmptcl φ x A C
12 8 11 readdd φ x A B + C = B + C
13 12 itgeq2dv φ A B + C dx = A B + C dx
14 8 recld φ x A B
15 8 iblcn φ x A B 𝐿 1 x A B 𝐿 1 x A B 𝐿 1
16 2 15 mpbid φ x A B 𝐿 1 x A B 𝐿 1
17 16 simpld φ x A B 𝐿 1
18 11 recld φ x A C
19 11 iblcn φ x A C 𝐿 1 x A C 𝐿 1 x A C 𝐿 1
20 4 19 mpbid φ x A C 𝐿 1 x A C 𝐿 1
21 20 simpld φ x A C 𝐿 1
22 8 11 addcld φ x A B + C
23 eqidd φ x A B + C = x A B + C
24 ref :
25 24 a1i φ :
26 25 feqmptd φ = y y
27 fveq2 y = B + C y = B + C
28 22 23 26 27 fmptco φ x A B + C = x A B + C
29 12 mpteq2dva φ x A B + C = x A B + C
30 28 29 eqtrd φ x A B + C = x A B + C
31 22 fmpttd φ x A B + C : A
32 ismbfcn x A B + C : A x A B + C MblFn x A B + C MblFn x A B + C MblFn
33 31 32 syl φ x A B + C MblFn x A B + C MblFn x A B + C MblFn
34 5 33 mpbid φ x A B + C MblFn x A B + C MblFn
35 34 simpld φ x A B + C MblFn
36 30 35 eqeltrrd φ x A B + C MblFn
37 14 17 18 21 36 14 18 itgaddnclem2 φ A B + C dx = A B dx + A C dx
38 13 37 eqtrd φ A B + C dx = A B dx + A C dx
39 8 11 imaddd φ x A B + C = B + C
40 39 itgeq2dv φ A B + C dx = A B + C dx
41 8 imcld φ x A B
42 16 simprd φ x A B 𝐿 1
43 11 imcld φ x A C
44 20 simprd φ x A C 𝐿 1
45 imf :
46 45 a1i φ :
47 46 feqmptd φ = y y
48 fveq2 y = B + C y = B + C
49 22 23 47 48 fmptco φ x A B + C = x A B + C
50 39 mpteq2dva φ x A B + C = x A B + C
51 49 50 eqtrd φ x A B + C = x A B + C
52 34 simprd φ x A B + C MblFn
53 51 52 eqeltrrd φ x A B + C MblFn
54 41 42 43 44 53 41 43 itgaddnclem2 φ A B + C dx = A B dx + A C dx
55 40 54 eqtrd φ A B + C dx = A B dx + A C dx
56 55 oveq2d φ i A B + C dx = i A B dx + A C dx
57 ax-icn i
58 57 a1i φ i
59 41 42 itgcl φ A B dx
60 43 44 itgcl φ A C dx
61 58 59 60 adddid φ i A B dx + A C dx = i A B dx + i A C dx
62 56 61 eqtrd φ i A B + C dx = i A B dx + i A C dx
63 38 62 oveq12d φ A B + C dx + i A B + C dx = A B dx + A C dx + i A B dx + i A C dx
64 14 17 itgcl φ A B dx
65 18 21 itgcl φ A C dx
66 mulcl i A B dx i A B dx
67 57 59 66 sylancr φ i A B dx
68 mulcl i A C dx i A C dx
69 57 60 68 sylancr φ i A C dx
70 64 65 67 69 add4d φ A B dx + A C dx + i A B dx + i A C dx = A B dx + i A B dx + A C dx + i A C dx
71 63 70 eqtrd φ A B + C dx + i A B + C dx = A B dx + i A B dx + A C dx + i A C dx
72 ovexd φ x A B + C V
73 1 2 3 4 5 ibladdnc φ x A B + C 𝐿 1
74 72 73 itgcnval φ A B + C dx = A B + C dx + i A B + C dx
75 1 2 itgcnval φ A B dx = A B dx + i A B dx
76 3 4 itgcnval φ A C dx = A C dx + i A C dx
77 75 76 oveq12d φ A B dx + A C dx = A B dx + i A B dx + A C dx + i A C dx
78 71 74 77 3eqtr4d φ A B + C dx = A B dx + A C dx