Description: The scalar product of a nonnegative real and a positive operator is a positive operator. Exercise 1(ii) of Retherford p. 49. (Contributed by NM, 25-Jul-2006) (New usage is discouraged.)
Ref | Expression | ||
---|---|---|---|
Assertion | leopmuli | |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | hmopre | |
|
2 | mulge0 | |
|
3 | 1 2 | sylanr1 | |
4 | 3 | expr | |
5 | 4 | an4s | |
6 | 5 | anassrs | |
7 | recn | |
|
8 | hmopf | |
|
9 | 7 8 | anim12i | |
10 | homval | |
|
11 | 10 | 3expa | |
12 | 11 | oveq1d | |
13 | simpll | |
|
14 | ffvelcdm | |
|
15 | 14 | adantll | |
16 | simpr | |
|
17 | ax-his3 | |
|
18 | 13 15 16 17 | syl3anc | |
19 | 12 18 | eqtrd | |
20 | 9 19 | sylan | |
21 | 20 | breq2d | |
22 | 21 | adantlr | |
23 | 6 22 | sylibrd | |
24 | 23 | ralimdva | |
25 | 24 | expimpd | |
26 | leoppos | |
|
27 | 26 | adantl | |
28 | 27 | anbi2d | |
29 | hmopm | |
|
30 | leoppos | |
|
31 | 29 30 | syl | |
32 | 25 28 31 | 3imtr4d | |
33 | 32 | imp | |