Metamath Proof Explorer


Theorem itgaddnc

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

Ref Expression
Hypotheses ibladdnc.1 φxABV
ibladdnc.2 φxAB𝐿1
ibladdnc.3 φxACV
ibladdnc.4 φxAC𝐿1
ibladdnc.m φxAB+CMblFn
Assertion itgaddnc φAB+Cdx=ABdx+ACdx

Proof

Step Hyp Ref Expression
1 ibladdnc.1 φxABV
2 ibladdnc.2 φxAB𝐿1
3 ibladdnc.3 φxACV
4 ibladdnc.4 φxAC𝐿1
5 ibladdnc.m φxAB+CMblFn
6 iblmbf xAB𝐿1xABMblFn
7 2 6 syl φxABMblFn
8 7 1 mbfmptcl φxAB
9 iblmbf xAC𝐿1xACMblFn
10 4 9 syl φxACMblFn
11 10 3 mbfmptcl φxAC
12 8 11 readdd φxAB+C=B+C
13 12 itgeq2dv φAB+Cdx=AB+Cdx
14 8 recld φxAB
15 8 iblcn φxAB𝐿1xAB𝐿1xAB𝐿1
16 2 15 mpbid φxAB𝐿1xAB𝐿1
17 16 simpld φxAB𝐿1
18 11 recld φxAC
19 11 iblcn φxAC𝐿1xAC𝐿1xAC𝐿1
20 4 19 mpbid φxAC𝐿1xAC𝐿1
21 20 simpld φxAC𝐿1
22 8 11 addcld φxAB+C
23 eqidd φxAB+C=xAB+C
24 ref :
25 24 a1i φ:
26 25 feqmptd φ=yy
27 fveq2 y=B+Cy=B+C
28 22 23 26 27 fmptco φxAB+C=xAB+C
29 12 mpteq2dva φxAB+C=xAB+C
30 28 29 eqtrd φxAB+C=xAB+C
31 22 fmpttd φxAB+C:A
32 ismbfcn xAB+C:AxAB+CMblFnxAB+CMblFnxAB+CMblFn
33 31 32 syl φxAB+CMblFnxAB+CMblFnxAB+CMblFn
34 5 33 mpbid φxAB+CMblFnxAB+CMblFn
35 34 simpld φxAB+CMblFn
36 30 35 eqeltrrd φxAB+CMblFn
37 14 17 18 21 36 14 18 itgaddnclem2 φAB+Cdx=ABdx+ACdx
38 13 37 eqtrd φAB+Cdx=ABdx+ACdx
39 8 11 imaddd φxAB+C=B+C
40 39 itgeq2dv φAB+Cdx=AB+Cdx
41 8 imcld φxAB
42 16 simprd φxAB𝐿1
43 11 imcld φxAC
44 20 simprd φxAC𝐿1
45 imf :
46 45 a1i φ:
47 46 feqmptd φ=yy
48 fveq2 y=B+Cy=B+C
49 22 23 47 48 fmptco φxAB+C=xAB+C
50 39 mpteq2dva φxAB+C=xAB+C
51 49 50 eqtrd φxAB+C=xAB+C
52 34 simprd φxAB+CMblFn
53 51 52 eqeltrrd φxAB+CMblFn
54 41 42 43 44 53 41 43 itgaddnclem2 φAB+Cdx=ABdx+ACdx
55 40 54 eqtrd φAB+Cdx=ABdx+ACdx
56 55 oveq2d φiAB+Cdx=iABdx+ACdx
57 ax-icn i
58 57 a1i φi
59 41 42 itgcl φABdx
60 43 44 itgcl φACdx
61 58 59 60 adddid φiABdx+ACdx=iABdx+iACdx
62 56 61 eqtrd φiAB+Cdx=iABdx+iACdx
63 38 62 oveq12d φAB+Cdx+iAB+Cdx=ABdx+ACdx+iABdx+iACdx
64 14 17 itgcl φABdx
65 18 21 itgcl φACdx
66 mulcl iABdxiABdx
67 57 59 66 sylancr φiABdx
68 mulcl iACdxiACdx
69 57 60 68 sylancr φiACdx
70 64 65 67 69 add4d φABdx+ACdx+iABdx+iACdx=ABdx+iABdx+ACdx+iACdx
71 63 70 eqtrd φAB+Cdx+iAB+Cdx=ABdx+iABdx+ACdx+iACdx
72 ovexd φxAB+CV
73 1 2 3 4 5 ibladdnc φxAB+C𝐿1
74 72 73 itgcnval φAB+Cdx=AB+Cdx+iAB+Cdx
75 1 2 itgcnval φABdx=ABdx+iABdx
76 3 4 itgcnval φACdx=ACdx+iACdx
77 75 76 oveq12d φABdx+ACdx=ABdx+iABdx+ACdx+iACdx
78 71 74 77 3eqtr4d φAB+Cdx=ABdx+ACdx