Step |
Hyp |
Ref |
Expression |
1 |
|
difss |
|
2 |
|
fssres |
|
3 |
1 2
|
mpan2 |
|
4 |
|
ffn |
|
5 |
|
fnresdm |
|
6 |
4 5
|
syl |
|
7 |
6
|
reseq1d |
|
8 |
|
resres |
|
9 |
|
invdif |
|
10 |
9
|
reseq2i |
|
11 |
8 10
|
eqtri |
|
12 |
7 11
|
eqtr3di |
|
13 |
12
|
feq1d |
|
14 |
3 13
|
mpbird |
|
15 |
14
|
adantl |
|
16 |
|
fsnunf2 |
|
17 |
15 16
|
syl3an1 |
|
18 |
|
simp1l |
|
19 |
|
simp3 |
|
20 |
|
setsval |
|
21 |
20
|
feq1d |
|
22 |
18 19 21
|
syl2anc |
|
23 |
17 22
|
mpbird |
|