Description: Division of both sides of 'less than or equal to' by a nonnegative number. (Contributed by Paul Chapman, 7-Sep-2007) (New usage is discouraged.) (Proof modification is discouraged.)
Ref | Expression | ||
---|---|---|---|
Assertion | lediv2aALT | |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | gt0ne0 | |
|
2 | rereccl | |
|
3 | 1 2 | syldan | |
4 | gt0ne0 | |
|
5 | rereccl | |
|
6 | 4 5 | syldan | |
7 | 3 6 | anim12i | |
8 | 7 | ancoms | |
9 | 8 | 3adant3 | |
10 | simp3 | |
|
11 | df-3an | |
|
12 | 9 10 11 | sylanbrc | |
13 | lemul2a | |
|
14 | 13 | ex | |
15 | 12 14 | syl | |
16 | lerec | |
|
17 | 16 | 3adant3 | |
18 | recn | |
|
19 | 18 | adantr | |
20 | recn | |
|
21 | 20 | adantr | |
22 | 21 1 | jca | |
23 | 19 22 | anim12i | |
24 | 3anass | |
|
25 | 23 24 | sylibr | |
26 | divrec | |
|
27 | 25 26 | syl | |
28 | 27 | ancoms | |
29 | 28 | 3adant1 | |
30 | recn | |
|
31 | 30 | adantr | |
32 | 31 4 | jca | |
33 | 19 32 | anim12i | |
34 | 3anass | |
|
35 | 33 34 | sylibr | |
36 | divrec | |
|
37 | 35 36 | syl | |
38 | 37 | ancoms | |
39 | 38 | 3adant2 | |
40 | 29 39 | breq12d | |
41 | 15 17 40 | 3imtr4d | |