| Step |
Hyp |
Ref |
Expression |
| 1 |
|
df-refld |
|
| 2 |
1
|
oveq1i |
|
| 3 |
|
resubdrg |
|
| 4 |
3
|
simpli |
|
| 5 |
|
nn0ssre |
|
| 6 |
|
ressabs |
|
| 7 |
4 5 6
|
mp2an |
|
| 8 |
2 7
|
eqtri |
|
| 9 |
|
retos |
|
| 10 |
|
rearchi |
|
| 11 |
9 10
|
pm3.2i |
|
| 12 |
|
nn0subm |
|
| 13 |
|
subrgsubg |
|
| 14 |
|
subgsubm |
|
| 15 |
4 13 14
|
mp2b |
|
| 16 |
1
|
subsubm |
|
| 17 |
15 16
|
ax-mp |
|
| 18 |
12 5 17
|
mpbir2an |
|
| 19 |
|
submarchi |
|
| 20 |
11 18 19
|
mp2an |
|
| 21 |
8 20
|
eqeltrri |
|