Metamath Proof Explorer


Definition df-qqh

Description: Define the canonical homomorphism from the rationals into any field. (Contributed by Mario Carneiro, 22-Oct-2017) (Revised by Thierry Arnoux, 23-Oct-2017)

Ref Expression
Assertion df-qqh ℚHom=rVranx,yℤRHomr-1UnitrxyℤRHomrx/rrℤRHomry

Detailed syntax breakdown

Step Hyp Ref Expression
0 cqqh classℚHom
1 vr setvarr
2 cvv classV
3 vx setvarx
4 cz class
5 vy setvary
6 czrh classℤRHom
7 1 cv setvarr
8 7 6 cfv classℤRHomr
9 8 ccnv classℤRHomr-1
10 cui classUnit
11 7 10 cfv classUnitr
12 9 11 cima classℤRHomr-1Unitr
13 3 cv setvarx
14 cdiv class÷
15 5 cv setvary
16 13 15 14 co classxy
17 13 8 cfv classℤRHomrx
18 cdvr class/r
19 7 18 cfv class/rr
20 15 8 cfv classℤRHomry
21 17 20 19 co classℤRHomrx/rrℤRHomry
22 16 21 cop classxyℤRHomrx/rrℤRHomry
23 3 5 4 12 22 cmpo classx,yℤRHomr-1UnitrxyℤRHomrx/rrℤRHomry
24 23 crn classranx,yℤRHomr-1UnitrxyℤRHomrx/rrℤRHomry
25 1 2 24 cmpt classrVranx,yℤRHomr-1UnitrxyℤRHomrx/rrℤRHomry
26 0 25 wceq wffℚHom=rVranx,yℤRHomr-1UnitrxyℤRHomrx/rrℤRHomry