Proof of Theorem sgnmul
Step | Hyp | Ref
| Expression |
1 | | remulcl 10021 |
. . 3
|
2 | 1 | rexrd 10089 |
. 2
|
3 | | eqeq1 2626 |
. 2
sgn
sgn sgn sgn sgn sgn |
4 | | eqeq1 2626 |
. 2
sgn
sgn sgn sgn sgn sgn |
5 | | eqeq1 2626 |
. 2
sgn sgn sgn sgn
sgn sgn |
6 | | fveq2 6191 |
. . . . . . 7
sgn sgn |
7 | | sgn0 13829 |
. . . . . . 7
sgn |
8 | 6, 7 | syl6eq 2672 |
. . . . . 6
sgn |
9 | 8 | oveq1d 6665 |
. . . . 5
sgn sgn sgn |
10 | 9 | adantl 482 |
. . . 4
sgn sgn sgn |
11 | | sgnclre 30601 |
. . . . . . 7
sgn |
12 | 11 | recnd 10068 |
. . . . . 6
sgn |
13 | 12 | mul02d 10234 |
. . . . 5
sgn |
14 | 13 | ad3antlr 767 |
. . . 4
sgn |
15 | 10, 14 | eqtr2d 2657 |
. . 3
sgn sgn |
16 | | fveq2 6191 |
. . . . . . 7
sgn sgn |
17 | 16, 7 | syl6eq 2672 |
. . . . . 6
sgn |
18 | 17 | oveq2d 6666 |
. . . . 5
sgn sgn sgn |
19 | 18 | adantl 482 |
. . . 4
sgn sgn sgn |
20 | | sgnclre 30601 |
. . . . . . 7
sgn |
21 | 20 | recnd 10068 |
. . . . . 6
sgn |
22 | 21 | mul01d 10235 |
. . . . 5
sgn |
23 | 22 | ad3antrrr 766 |
. . . 4
sgn |
24 | 19, 23 | eqtr2d 2657 |
. . 3
sgn sgn |
25 | | simpl 473 |
. . . . . 6
|
26 | 25 | recnd 10068 |
. . . . 5
|
27 | | simpr 477 |
. . . . . 6
|
28 | 27 | recnd 10068 |
. . . . 5
|
29 | 26, 28 | mul0ord 10677 |
. . . 4
|
30 | 29 | biimpa 501 |
. . 3
|
31 | 15, 24, 30 | mpjaodan 827 |
. 2
sgn sgn |
32 | | simpll 790 |
. . . 4
|
33 | 32 | rexrd 10089 |
. . 3
|
34 | | oveq1 6657 |
. . . 4
sgn
sgn sgn sgn |
35 | 34 | eqeq2d 2632 |
. . 3
sgn
sgn sgn
sgn |
36 | | oveq1 6657 |
. . . 4
sgn
sgn sgn sgn |
37 | 36 | eqeq2d 2632 |
. . 3
sgn
sgn sgn
sgn |
38 | | oveq1 6657 |
. . . 4
sgn sgn sgn sgn |
39 | 38 | eqeq2d 2632 |
. . 3
sgn sgn sgn sgn |
40 | | simpr 477 |
. . . 4
|
41 | 26 | adantr 481 |
. . . . . . 7
|
42 | 28 | adantr 481 |
. . . . . . 7
|
43 | | simpr 477 |
. . . . . . . 8
|
44 | 43 | gt0ne0d 10592 |
. . . . . . 7
|
45 | 41, 42, 44 | mulne0bad 10682 |
. . . . . 6
|
46 | 45 | neneqd 2799 |
. . . . 5
|
47 | 46 | adantr 481 |
. . . 4
|
48 | 40, 47 | pm2.21dd 186 |
. . 3
sgn |
49 | 27 | ad2antrr 762 |
. . . . . . 7
|
50 | 49 | rexrd 10089 |
. . . . . 6
|
51 | | simpll 790 |
. . . . . . 7
|
52 | | 0red 10041 |
. . . . . . . 8
|
53 | | simplll 798 |
. . . . . . . 8
|
54 | | simpr 477 |
. . . . . . . 8
|
55 | 52, 53, 54 | ltled 10185 |
. . . . . . 7
|
56 | | simplr 792 |
. . . . . . 7
|
57 | | prodgt0 10868 |
. . . . . . 7
|
58 | 51, 55, 56, 57 | syl12anc 1324 |
. . . . . 6
|
59 | | sgnp 13830 |
. . . . . 6
sgn |
60 | 50, 58, 59 | syl2anc 693 |
. . . . 5
sgn |
61 | 60 | oveq2d 6666 |
. . . 4
sgn |
62 | | 1t1e1 11175 |
. . . 4
|
63 | 61, 62 | syl6req 2673 |
. . 3
sgn |
64 | 27 | ad2antrr 762 |
. . . . . . 7
|
65 | 64 | rexrd 10089 |
. . . . . 6
|
66 | | simplll 798 |
. . . . . . . . 9
|
67 | 66 | renegcld 10457 |
. . . . . . . 8
|
68 | 64 | renegcld 10457 |
. . . . . . . 8
|
69 | | 0red 10041 |
. . . . . . . . 9
|
70 | | simpr 477 |
. . . . . . . . . 10
|
71 | 25 | lt0neg1d 10597 |
. . . . . . . . . . 11
|
72 | 71 | ad2antrr 762 |
. . . . . . . . . 10
|
73 | 70, 72 | mpbid 222 |
. . . . . . . . 9
|
74 | 69, 67, 73 | ltled 10185 |
. . . . . . . 8
|
75 | | simplr 792 |
. . . . . . . . 9
|
76 | 26 | ad2antrr 762 |
. . . . . . . . . 10
|
77 | 28 | ad2antrr 762 |
. . . . . . . . . 10
|
78 | 76, 77 | mul2negd 10485 |
. . . . . . . . 9
|
79 | 75, 78 | breqtrrd 4681 |
. . . . . . . 8
|
80 | | prodgt0 10868 |
. . . . . . . 8
|
81 | 67, 68, 74, 79, 80 | syl22anc 1327 |
. . . . . . 7
|
82 | 27 | lt0neg1d 10597 |
. . . . . . . 8
|
83 | 82 | ad2antrr 762 |
. . . . . . 7
|
84 | 81, 83 | mpbird 247 |
. . . . . 6
|
85 | | sgnn 13834 |
. . . . . 6
sgn |
86 | 65, 84, 85 | syl2anc 693 |
. . . . 5
sgn |
87 | 86 | oveq2d 6666 |
. . . 4
sgn |
88 | | neg1mulneg1e1 11245 |
. . . 4
|
89 | 87, 88 | syl6req 2673 |
. . 3
sgn |
90 | 33, 35, 37, 39, 48, 63, 89 | sgn3da 30603 |
. 2
sgn sgn |
91 | | simpll 790 |
. . . 4
|
92 | 91 | rexrd 10089 |
. . 3
|
93 | 34 | eqeq2d 2632 |
. . 3
sgn
sgn sgn
sgn |
94 | 36 | eqeq2d 2632 |
. . 3
sgn
sgn sgn
sgn |
95 | 38 | eqeq2d 2632 |
. . 3
sgn sgn sgn sgn |
96 | | simpr 477 |
. . . 4
|
97 | 26 | ad2antrr 762 |
. . . . . 6
|
98 | 28 | ad2antrr 762 |
. . . . . 6
|
99 | | simplr 792 |
. . . . . . 7
|
100 | 99 | lt0ne0d 10593 |
. . . . . 6
|
101 | 97, 98, 100 | mulne0bad 10682 |
. . . . 5
|
102 | 101 | neneqd 2799 |
. . . 4
|
103 | 96, 102 | pm2.21dd 186 |
. . 3
sgn |
104 | 27 | ad2antrr 762 |
. . . . . . 7
|
105 | 104 | rexrd 10089 |
. . . . . 6
|
106 | | simplr 792 |
. . . . . . 7
|
107 | 26, 28 | mulcomd 10061 |
. . . . . . . . 9
|
108 | 107 | breq1d 4663 |
. . . . . . . 8
|
109 | 108 | biimpa 501 |
. . . . . . 7
|
110 | 106, 91, 109 | mul2lt0rgt0 11933 |
. . . . . 6
|
111 | 105, 110,
85 | syl2anc 693 |
. . . . 5
sgn |
112 | 111 | oveq2d 6666 |
. . . 4
sgn |
113 | | neg1cn 11124 |
. . . . 5
|
114 | 113 | mulid2i 10043 |
. . . 4
|
115 | 112, 114 | syl6req 2673 |
. . 3
sgn |
116 | 106 | adantr 481 |
. . . . . . 7
|
117 | 116 | rexrd 10089 |
. . . . . 6
|
118 | 106, 91, 109 | mul2lt0rlt0 11932 |
. . . . . 6
|
119 | 117, 118,
59 | syl2anc 693 |
. . . . 5
sgn |
120 | 119 | oveq2d 6666 |
. . . 4
sgn |
121 | 113 | mulid1i 10042 |
. . . 4
|
122 | 120, 121 | syl6req 2673 |
. . 3
sgn |
123 | 92, 93, 94, 95, 103, 115, 122 | sgn3da 30603 |
. 2
sgn sgn |
124 | 2, 3, 4, 5, 31, 90, 123 | sgn3da 30603 |
1
sgn sgn sgn |