Metamath Proof Explorer


Theorem cvmliftiota

Description: Write out a function H that is the unique lift of F . (Contributed by Mario Carneiro, 16-Feb-2015)

Ref Expression
Hypotheses cvmliftiota.b B = C
cvmliftiota.h H = ι f II Cn C | F f = G f 0 = P
cvmliftiota.f φ F C CovMap J
cvmliftiota.g φ G II Cn J
cvmliftiota.p φ P B
cvmliftiota.e φ F P = G 0
Assertion cvmliftiota φ H II Cn C F H = G H 0 = P

Proof

Step Hyp Ref Expression
1 cvmliftiota.b B = C
2 cvmliftiota.h H = ι f II Cn C | F f = G f 0 = P
3 cvmliftiota.f φ F C CovMap J
4 cvmliftiota.g φ G II Cn J
5 cvmliftiota.p φ P B
6 cvmliftiota.e φ F P = G 0
7 coeq2 f = g F f = F g
8 7 eqeq1d f = g F f = G F g = G
9 fveq1 f = g f 0 = g 0
10 9 eqeq1d f = g f 0 = P g 0 = P
11 8 10 anbi12d f = g F f = G f 0 = P F g = G g 0 = P
12 11 cbvriotavw ι f II Cn C | F f = G f 0 = P = ι g II Cn C | F g = G g 0 = P
13 2 12 eqtri H = ι g II Cn C | F g = G g 0 = P
14 1 cvmlift F C CovMap J G II Cn J P B F P = G 0 ∃! g II Cn C F g = G g 0 = P
15 3 4 5 6 14 syl22anc φ ∃! g II Cn C F g = G g 0 = P
16 riotacl2 ∃! g II Cn C F g = G g 0 = P ι g II Cn C | F g = G g 0 = P g II Cn C | F g = G g 0 = P
17 15 16 syl φ ι g II Cn C | F g = G g 0 = P g II Cn C | F g = G g 0 = P
18 13 17 eqeltrid φ H g II Cn C | F g = G g 0 = P
19 coeq2 g = H F g = F H
20 19 eqeq1d g = H F g = G F H = G
21 fveq1 g = H g 0 = H 0
22 21 eqeq1d g = H g 0 = P H 0 = P
23 20 22 anbi12d g = H F g = G g 0 = P F H = G H 0 = P
24 23 elrab H g II Cn C | F g = G g 0 = P H II Cn C F H = G H 0 = P
25 3anass H II Cn C F H = G H 0 = P H II Cn C F H = G H 0 = P
26 24 25 bitr4i H g II Cn C | F g = G g 0 = P H II Cn C F H = G H 0 = P
27 18 26 sylib φ H II Cn C F H = G H 0 = P