Step |
Hyp |
Ref |
Expression |
1 |
|
cnfldbas |
|
2 |
1
|
a1i |
|
3 |
|
cnfldmul |
|
4 |
3
|
a1i |
|
5 |
|
cnfld0 |
|
6 |
5
|
a1i |
|
7 |
|
cnfld1 |
|
8 |
7
|
a1i |
|
9 |
|
cnring |
|
10 |
9
|
a1i |
|
11 |
|
mulne0 |
|
12 |
11
|
3adant1 |
|
13 |
|
ax-1ne0 |
|
14 |
13
|
a1i |
|
15 |
|
reccl |
|
16 |
15
|
adantl |
|
17 |
|
recne0 |
|
18 |
17
|
adantl |
|
19 |
|
recid2 |
|
20 |
19
|
adantl |
|
21 |
2 4 6 8 10 12 14 16 18 20
|
isdrngd |
|
22 |
21
|
mptru |
|