Step |
Hyp |
Ref |
Expression |
1 |
|
dgreq.1 |
|
2 |
|
dgreq.2 |
|
3 |
|
dgreq.3 |
|
4 |
|
dgreq.4 |
|
5 |
|
dgreq.5 |
|
6 |
|
dgreq.6 |
|
7 |
|
elfznn0 |
|
8 |
|
ffvelrn |
|
9 |
3 7 8
|
syl2an |
|
10 |
1 2 9 5
|
dgrle |
|
11 |
1 2 3 4 5
|
coeeq |
|
12 |
11
|
fveq1d |
|
13 |
12 6
|
eqnetrd |
|
14 |
|
eqid |
|
15 |
|
eqid |
|
16 |
14 15
|
dgrub |
|
17 |
1 2 13 16
|
syl3anc |
|
18 |
|
dgrcl |
|
19 |
1 18
|
syl |
|
20 |
19
|
nn0red |
|
21 |
2
|
nn0red |
|
22 |
20 21
|
letri3d |
|
23 |
10 17 22
|
mpbir2and |
|