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=IndMetU
vmcn.j J=MetOpenC
vmcn.m M=-vU
Assertion vmcn UNrmCVecMJ×tJCnJ

Proof

Step Hyp Ref Expression
1 vmcn.c C=IndMetU
2 vmcn.j J=MetOpenC
3 vmcn.m M=-vU
4 eqid BaseSetU=BaseSetU
5 eqid +vU=+vU
6 eqid 𝑠OLDU=𝑠OLDU
7 4 5 6 3 nvmfval UNrmCVecM=xBaseSetU,yBaseSetUx+vU-1𝑠OLDUy
8 4 1 imsxmet UNrmCVecC∞MetBaseSetU
9 2 mopntopon C∞MetBaseSetUJTopOnBaseSetU
10 8 9 syl UNrmCVecJTopOnBaseSetU
11 10 10 cnmpt1st UNrmCVecxBaseSetU,yBaseSetUxJ×tJCnJ
12 eqid TopOpenfld=TopOpenfld
13 12 cnfldtopon TopOpenfldTopOn
14 13 a1i UNrmCVecTopOpenfldTopOn
15 neg1cn 1
16 15 a1i UNrmCVec1
17 10 10 14 16 cnmpt2c UNrmCVecxBaseSetU,yBaseSetU1J×tJCnTopOpenfld
18 10 10 cnmpt2nd UNrmCVecxBaseSetU,yBaseSetUyJ×tJCnJ
19 1 2 6 12 smcn UNrmCVec𝑠OLDUTopOpenfld×tJCnJ
20 10 10 17 18 19 cnmpt22f UNrmCVecxBaseSetU,yBaseSetU-1𝑠OLDUyJ×tJCnJ
21 1 2 5 vacn UNrmCVec+vUJ×tJCnJ
22 10 10 11 20 21 cnmpt22f UNrmCVecxBaseSetU,yBaseSetUx+vU-1𝑠OLDUyJ×tJCnJ
23 7 22 eqeltrd UNrmCVecMJ×tJCnJ