Description: In a unital ring the multiplication is a monoid. (Contributed by FL, 24-Jan-2010) (Revised by Mario Carneiro, 22-Dec-2013) (New usage is discouraged.)
Ref | Expression | ||
---|---|---|---|
Hypothesis | unmnd.1 | |
|
Assertion | rngomndo | |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | unmnd.1 | |
|
2 | eqid | |
|
3 | eqid | |
|
4 | 2 1 3 | rngosm | |
5 | 2 1 3 | rngoass | |
6 | 5 | ralrimivvva | |
7 | 2 1 3 | rngoi | |
8 | 7 | simprrd | |
9 | 1 2 | rngorn1 | |
10 | xpid11 | |
|
11 | 10 | biimpri | |
12 | feq23 | |
|
13 | 11 12 | mpancom | |
14 | raleq | |
|
15 | 14 | raleqbi1dv | |
16 | 15 | raleqbi1dv | |
17 | raleq | |
|
18 | 17 | rexeqbi1dv | |
19 | 13 16 18 | 3anbi123d | |
20 | 19 | eqcoms | |
21 | 9 20 | syl | |
22 | 4 6 8 21 | mpbir3and | |
23 | fvex | |
|
24 | eleq1 | |
|
25 | 23 24 | mpbiri | |
26 | eqid | |
|
27 | 26 | ismndo1 | |
28 | 1 25 27 | mp2b | |
29 | 22 28 | sylibr | |