Metamath Proof Explorer


Theorem normlem9

Description: Lemma used to derive properties of norm. (Contributed by NM, 30-Jun-2005) (New usage is discouraged.)

Ref Expression
Hypotheses normlem8.1 A
normlem8.2 B
normlem8.3 C
normlem8.4 D
Assertion normlem9 A - B ih C - D = A ih C + B ih D - A ih D + B ih C

Proof

Step Hyp Ref Expression
1 normlem8.1 A
2 normlem8.2 B
3 normlem8.3 C
4 normlem8.4 D
5 1 2 hvsubvali A - B = A + -1 B
6 3 4 hvsubvali C - D = C + -1 D
7 5 6 oveq12i A - B ih C - D = A + -1 B ih C + -1 D
8 neg1cn 1
9 8 2 hvmulcli -1 B
10 8 4 hvmulcli -1 D
11 1 9 3 10 normlem8 A + -1 B ih C + -1 D = A ih C + -1 B ih -1 D + A ih -1 D + -1 B ih C
12 ax-his3 1 B -1 D -1 B ih -1 D = -1 B ih -1 D
13 8 2 10 12 mp3an -1 B ih -1 D = -1 B ih -1 D
14 his5 1 B D B ih -1 D = 1 B ih D
15 8 2 4 14 mp3an B ih -1 D = 1 B ih D
16 15 oveq2i -1 B ih -1 D = -1 1 B ih D
17 neg1rr 1
18 cjre 1 1 = 1
19 17 18 ax-mp 1 = 1
20 19 oveq2i -1 1 = -1 -1
21 ax-1cn 1
22 21 21 mul2negi -1 -1 = 1 1
23 21 mulid2i 1 1 = 1
24 20 22 23 3eqtri -1 1 = 1
25 24 oveq1i -1 1 B ih D = 1 B ih D
26 8 cjcli 1
27 2 4 hicli B ih D
28 8 26 27 mulassi -1 1 B ih D = -1 1 B ih D
29 27 mulid2i 1 B ih D = B ih D
30 25 28 29 3eqtr3i -1 1 B ih D = B ih D
31 13 16 30 3eqtri -1 B ih -1 D = B ih D
32 31 oveq2i A ih C + -1 B ih -1 D = A ih C + B ih D
33 his5 1 A D A ih -1 D = 1 A ih D
34 8 1 4 33 mp3an A ih -1 D = 1 A ih D
35 19 oveq1i 1 A ih D = -1 A ih D
36 1 4 hicli A ih D
37 36 mulm1i -1 A ih D = A ih D
38 34 35 37 3eqtri A ih -1 D = A ih D
39 ax-his3 1 B C -1 B ih C = -1 B ih C
40 8 2 3 39 mp3an -1 B ih C = -1 B ih C
41 2 3 hicli B ih C
42 41 mulm1i -1 B ih C = B ih C
43 40 42 eqtri -1 B ih C = B ih C
44 38 43 oveq12i A ih -1 D + -1 B ih C = - A ih D + B ih C
45 36 41 negdii A ih D + B ih C = - A ih D + B ih C
46 44 45 eqtr4i A ih -1 D + -1 B ih C = A ih D + B ih C
47 32 46 oveq12i A ih C + -1 B ih -1 D + A ih -1 D + -1 B ih C = A ih C + B ih D + A ih D + B ih C
48 1 3 hicli A ih C
49 48 27 addcli A ih C + B ih D
50 36 41 addcli A ih D + B ih C
51 49 50 negsubi A ih C + B ih D + A ih D + B ih C = A ih C + B ih D - A ih D + B ih C
52 47 51 eqtri A ih C + -1 B ih -1 D + A ih -1 D + -1 B ih C = A ih C + B ih D - A ih D + B ih C
53 7 11 52 3eqtri A - B ih C - D = A ih C + B ih D - A ih D + B ih C