Metamath Proof Explorer


Theorem fndmfifsupp

Description: A function with a finite domain is always finitely supported. (Contributed by AV, 25-May-2019)

Ref Expression
Hypotheses fndmfisuppfi.f φFFnD
fndmfisuppfi.d φDFin
fndmfisuppfi.z φZV
Assertion fndmfifsupp φfinSuppZF

Proof

Step Hyp Ref Expression
1 fndmfisuppfi.f φFFnD
2 fndmfisuppfi.d φDFin
3 fndmfisuppfi.z φZV
4 dffn3 FFnDF:DranF
5 1 4 sylib φF:DranF
6 5 2 3 fdmfifsupp φfinSuppZF