| Step |
Hyp |
Ref |
Expression |
| 1 |
|
logcn.d |
|- D = ( CC \ ( -oo (,] 0 ) ) |
| 2 |
1
|
eleq2i |
|- ( A e. D <-> A e. ( CC \ ( -oo (,] 0 ) ) ) |
| 3 |
|
eldif |
|- ( A e. ( CC \ ( -oo (,] 0 ) ) <-> ( A e. CC /\ -. A e. ( -oo (,] 0 ) ) ) |
| 4 |
|
mnfxr |
|- -oo e. RR* |
| 5 |
|
0re |
|- 0 e. RR |
| 6 |
|
elioc2 |
|- ( ( -oo e. RR* /\ 0 e. RR ) -> ( A e. ( -oo (,] 0 ) <-> ( A e. RR /\ -oo < A /\ A <_ 0 ) ) ) |
| 7 |
4 5 6
|
mp2an |
|- ( A e. ( -oo (,] 0 ) <-> ( A e. RR /\ -oo < A /\ A <_ 0 ) ) |
| 8 |
|
df-3an |
|- ( ( A e. RR /\ -oo < A /\ A <_ 0 ) <-> ( ( A e. RR /\ -oo < A ) /\ A <_ 0 ) ) |
| 9 |
|
mnflt |
|- ( A e. RR -> -oo < A ) |
| 10 |
9
|
pm4.71i |
|- ( A e. RR <-> ( A e. RR /\ -oo < A ) ) |
| 11 |
10
|
anbi1i |
|- ( ( A e. RR /\ A <_ 0 ) <-> ( ( A e. RR /\ -oo < A ) /\ A <_ 0 ) ) |
| 12 |
|
lenlt |
|- ( ( A e. RR /\ 0 e. RR ) -> ( A <_ 0 <-> -. 0 < A ) ) |
| 13 |
5 12
|
mpan2 |
|- ( A e. RR -> ( A <_ 0 <-> -. 0 < A ) ) |
| 14 |
|
elrp |
|- ( A e. RR+ <-> ( A e. RR /\ 0 < A ) ) |
| 15 |
14
|
baib |
|- ( A e. RR -> ( A e. RR+ <-> 0 < A ) ) |
| 16 |
15
|
notbid |
|- ( A e. RR -> ( -. A e. RR+ <-> -. 0 < A ) ) |
| 17 |
13 16
|
bitr4d |
|- ( A e. RR -> ( A <_ 0 <-> -. A e. RR+ ) ) |
| 18 |
17
|
pm5.32i |
|- ( ( A e. RR /\ A <_ 0 ) <-> ( A e. RR /\ -. A e. RR+ ) ) |
| 19 |
11 18
|
bitr3i |
|- ( ( ( A e. RR /\ -oo < A ) /\ A <_ 0 ) <-> ( A e. RR /\ -. A e. RR+ ) ) |
| 20 |
7 8 19
|
3bitri |
|- ( A e. ( -oo (,] 0 ) <-> ( A e. RR /\ -. A e. RR+ ) ) |
| 21 |
20
|
notbii |
|- ( -. A e. ( -oo (,] 0 ) <-> -. ( A e. RR /\ -. A e. RR+ ) ) |
| 22 |
|
iman |
|- ( ( A e. RR -> A e. RR+ ) <-> -. ( A e. RR /\ -. A e. RR+ ) ) |
| 23 |
21 22
|
bitr4i |
|- ( -. A e. ( -oo (,] 0 ) <-> ( A e. RR -> A e. RR+ ) ) |
| 24 |
23
|
anbi2i |
|- ( ( A e. CC /\ -. A e. ( -oo (,] 0 ) ) <-> ( A e. CC /\ ( A e. RR -> A e. RR+ ) ) ) |
| 25 |
2 3 24
|
3bitri |
|- ( A e. D <-> ( A e. CC /\ ( A e. RR -> A e. RR+ ) ) ) |