Metamath Proof Explorer


Theorem vmcn

Description: Vector subtraction is jointly continuous in both arguments. (Contributed by Mario Carneiro, 6-May-2014) (New usage is discouraged.)

Ref Expression
Hypotheses vmcn.c C = IndMet U
vmcn.j J = MetOpen C
vmcn.m M = - v U
Assertion vmcn U NrmCVec M J × t J Cn J

Proof

Step Hyp Ref Expression
1 vmcn.c C = IndMet U
2 vmcn.j J = MetOpen C
3 vmcn.m M = - v U
4 eqid BaseSet U = BaseSet U
5 eqid + v U = + v U
6 eqid 𝑠OLD U = 𝑠OLD U
7 4 5 6 3 nvmfval U NrmCVec M = x BaseSet U , y BaseSet U x + v U -1 𝑠OLD U y
8 4 1 imsxmet U NrmCVec C ∞Met BaseSet U
9 2 mopntopon C ∞Met BaseSet U J TopOn BaseSet U
10 8 9 syl U NrmCVec J TopOn BaseSet U
11 10 10 cnmpt1st U NrmCVec x BaseSet U , y BaseSet U x J × t J Cn J
12 eqid TopOpen fld = TopOpen fld
13 12 cnfldtopon TopOpen fld TopOn
14 13 a1i U NrmCVec TopOpen fld TopOn
15 neg1cn 1
16 15 a1i U NrmCVec 1
17 10 10 14 16 cnmpt2c U NrmCVec x BaseSet U , y BaseSet U 1 J × t J Cn TopOpen fld
18 10 10 cnmpt2nd U NrmCVec x BaseSet U , y BaseSet U y J × t J Cn J
19 1 2 6 12 smcn U NrmCVec 𝑠OLD U TopOpen fld × t J Cn J
20 10 10 17 18 19 cnmpt22f U NrmCVec x BaseSet U , y BaseSet U -1 𝑠OLD U y J × t J Cn J
21 1 2 5 vacn U NrmCVec + v U J × t J Cn J
22 10 10 11 20 21 cnmpt22f U NrmCVec x BaseSet U , y BaseSet U x + v U -1 𝑠OLD U y J × t J Cn J
23 7 22 eqeltrd U NrmCVec M J × t J Cn J