Step |
Hyp |
Ref |
Expression |
1 |
|
hashf |
|- # : _V --> ( NN0 u. { +oo } ) |
2 |
|
nn0z |
|- ( x e. NN0 -> x e. ZZ ) |
3 |
|
zre |
|- ( x e. ZZ -> x e. RR ) |
4 |
|
rexr |
|- ( x e. RR -> x e. RR* ) |
5 |
2 3 4
|
3syl |
|- ( x e. NN0 -> x e. RR* ) |
6 |
|
nn0ge0 |
|- ( x e. NN0 -> 0 <_ x ) |
7 |
|
elxrge0 |
|- ( x e. ( 0 [,] +oo ) <-> ( x e. RR* /\ 0 <_ x ) ) |
8 |
5 6 7
|
sylanbrc |
|- ( x e. NN0 -> x e. ( 0 [,] +oo ) ) |
9 |
8
|
ssriv |
|- NN0 C_ ( 0 [,] +oo ) |
10 |
|
0xr |
|- 0 e. RR* |
11 |
|
pnfxr |
|- +oo e. RR* |
12 |
|
0lepnf |
|- 0 <_ +oo |
13 |
|
ubicc2 |
|- ( ( 0 e. RR* /\ +oo e. RR* /\ 0 <_ +oo ) -> +oo e. ( 0 [,] +oo ) ) |
14 |
10 11 12 13
|
mp3an |
|- +oo e. ( 0 [,] +oo ) |
15 |
|
snssi |
|- ( +oo e. ( 0 [,] +oo ) -> { +oo } C_ ( 0 [,] +oo ) ) |
16 |
14 15
|
ax-mp |
|- { +oo } C_ ( 0 [,] +oo ) |
17 |
9 16
|
unssi |
|- ( NN0 u. { +oo } ) C_ ( 0 [,] +oo ) |
18 |
|
fss |
|- ( ( # : _V --> ( NN0 u. { +oo } ) /\ ( NN0 u. { +oo } ) C_ ( 0 [,] +oo ) ) -> # : _V --> ( 0 [,] +oo ) ) |
19 |
1 17 18
|
mp2an |
|- # : _V --> ( 0 [,] +oo ) |