Description: Define poset meet. (Contributed by NM, 12-Sep-2011) (Revised by NM, 8-Sep-2018)
Ref | Expression | ||
---|---|---|---|
Assertion | df-meet | |- meet = ( p e. _V |-> { <. <. x , y >. , z >. | { x , y } ( glb ` p ) z } ) |
Step | Hyp | Ref | Expression |
---|---|---|---|
0 | cmee | |- meet |
|
1 | vp | |- p |
|
2 | cvv | |- _V |
|
3 | vx | |- x |
|
4 | vy | |- y |
|
5 | vz | |- z |
|
6 | 3 | cv | |- x |
7 | 4 | cv | |- y |
8 | 6 7 | cpr | |- { x , y } |
9 | cglb | |- glb |
|
10 | 1 | cv | |- p |
11 | 10 9 | cfv | |- ( glb ` p ) |
12 | 5 | cv | |- z |
13 | 8 12 11 | wbr | |- { x , y } ( glb ` p ) z |
14 | 13 3 4 5 | coprab | |- { <. <. x , y >. , z >. | { x , y } ( glb ` p ) z } |
15 | 1 2 14 | cmpt | |- ( p e. _V |-> { <. <. x , y >. , z >. | { x , y } ( glb ` p ) z } ) |
16 | 0 15 | wceq | |- meet = ( p e. _V |-> { <. <. x , y >. , z >. | { x , y } ( glb ` p ) z } ) |