Description: Define completely normal spaces. A space is completely normal if all its subspaces are normal. (Contributed by Mario Carneiro, 26-Aug-2015)
| Ref | Expression | ||
|---|---|---|---|
| Assertion | df-cnrm | |- CNrm = { j e. Top | A. x e. ~P U. j ( j |`t x ) e. Nrm } |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 0 | ccnrm | |- CNrm |
|
| 1 | vj | |- j |
|
| 2 | ctop | |- Top |
|
| 3 | vx | |- x |
|
| 4 | 1 | cv | |- j |
| 5 | 4 | cuni | |- U. j |
| 6 | 5 | cpw | |- ~P U. j |
| 7 | crest | |- |`t |
|
| 8 | 3 | cv | |- x |
| 9 | 4 8 7 | co | |- ( j |`t x ) |
| 10 | cnrm | |- Nrm |
|
| 11 | 9 10 | wcel | |- ( j |`t x ) e. Nrm |
| 12 | 11 3 6 | wral | |- A. x e. ~P U. j ( j |`t x ) e. Nrm |
| 13 | 12 1 2 | crab | |- { j e. Top | A. x e. ~P U. j ( j |`t x ) e. Nrm } |
| 14 | 0 13 | wceq | |- CNrm = { j e. Top | A. x e. ~P U. j ( j |`t x ) e. Nrm } |