Metamath Proof Explorer


Theorem rmfsupp

Description: A mapping of a multiplication of a constant with a function into a ring is finitely supported if the function is finitely supported. (Contributed by AV, 9-Jun-2019)

Ref Expression
Hypothesis rmsuppfi.r 𝑅 = ( Base ‘ 𝑀 )
Assertion rmfsupp ( ( ( 𝑀 ∈ Ring ∧ 𝑉𝑋𝐶𝑅 ) ∧ 𝐴 ∈ ( 𝑅m 𝑉 ) ∧ 𝐴 finSupp ( 0g𝑀 ) ) → ( 𝑣𝑉 ↦ ( 𝐶 ( .r𝑀 ) ( 𝐴𝑣 ) ) ) finSupp ( 0g𝑀 ) )

Proof

Step Hyp Ref Expression
1 rmsuppfi.r 𝑅 = ( Base ‘ 𝑀 )
2 funmpt Fun ( 𝑣𝑉 ↦ ( 𝐶 ( .r𝑀 ) ( 𝐴𝑣 ) ) )
3 2 a1i ( ( ( 𝑀 ∈ Ring ∧ 𝑉𝑋𝐶𝑅 ) ∧ 𝐴 ∈ ( 𝑅m 𝑉 ) ∧ 𝐴 finSupp ( 0g𝑀 ) ) → Fun ( 𝑣𝑉 ↦ ( 𝐶 ( .r𝑀 ) ( 𝐴𝑣 ) ) ) )
4 id ( 𝐴 finSupp ( 0g𝑀 ) → 𝐴 finSupp ( 0g𝑀 ) )
5 4 fsuppimpd ( 𝐴 finSupp ( 0g𝑀 ) → ( 𝐴 supp ( 0g𝑀 ) ) ∈ Fin )
6 1 rmsuppfi ( ( ( 𝑀 ∈ Ring ∧ 𝑉𝑋𝐶𝑅 ) ∧ 𝐴 ∈ ( 𝑅m 𝑉 ) ∧ ( 𝐴 supp ( 0g𝑀 ) ) ∈ Fin ) → ( ( 𝑣𝑉 ↦ ( 𝐶 ( .r𝑀 ) ( 𝐴𝑣 ) ) ) supp ( 0g𝑀 ) ) ∈ Fin )
7 5 6 syl3an3 ( ( ( 𝑀 ∈ Ring ∧ 𝑉𝑋𝐶𝑅 ) ∧ 𝐴 ∈ ( 𝑅m 𝑉 ) ∧ 𝐴 finSupp ( 0g𝑀 ) ) → ( ( 𝑣𝑉 ↦ ( 𝐶 ( .r𝑀 ) ( 𝐴𝑣 ) ) ) supp ( 0g𝑀 ) ) ∈ Fin )
8 mptexg ( 𝑉𝑋 → ( 𝑣𝑉 ↦ ( 𝐶 ( .r𝑀 ) ( 𝐴𝑣 ) ) ) ∈ V )
9 8 3ad2ant2 ( ( 𝑀 ∈ Ring ∧ 𝑉𝑋𝐶𝑅 ) → ( 𝑣𝑉 ↦ ( 𝐶 ( .r𝑀 ) ( 𝐴𝑣 ) ) ) ∈ V )
10 9 3ad2ant1 ( ( ( 𝑀 ∈ Ring ∧ 𝑉𝑋𝐶𝑅 ) ∧ 𝐴 ∈ ( 𝑅m 𝑉 ) ∧ 𝐴 finSupp ( 0g𝑀 ) ) → ( 𝑣𝑉 ↦ ( 𝐶 ( .r𝑀 ) ( 𝐴𝑣 ) ) ) ∈ V )
11 fvex ( 0g𝑀 ) ∈ V
12 isfsupp ( ( ( 𝑣𝑉 ↦ ( 𝐶 ( .r𝑀 ) ( 𝐴𝑣 ) ) ) ∈ V ∧ ( 0g𝑀 ) ∈ V ) → ( ( 𝑣𝑉 ↦ ( 𝐶 ( .r𝑀 ) ( 𝐴𝑣 ) ) ) finSupp ( 0g𝑀 ) ↔ ( Fun ( 𝑣𝑉 ↦ ( 𝐶 ( .r𝑀 ) ( 𝐴𝑣 ) ) ) ∧ ( ( 𝑣𝑉 ↦ ( 𝐶 ( .r𝑀 ) ( 𝐴𝑣 ) ) ) supp ( 0g𝑀 ) ) ∈ Fin ) ) )
13 10 11 12 sylancl ( ( ( 𝑀 ∈ Ring ∧ 𝑉𝑋𝐶𝑅 ) ∧ 𝐴 ∈ ( 𝑅m 𝑉 ) ∧ 𝐴 finSupp ( 0g𝑀 ) ) → ( ( 𝑣𝑉 ↦ ( 𝐶 ( .r𝑀 ) ( 𝐴𝑣 ) ) ) finSupp ( 0g𝑀 ) ↔ ( Fun ( 𝑣𝑉 ↦ ( 𝐶 ( .r𝑀 ) ( 𝐴𝑣 ) ) ) ∧ ( ( 𝑣𝑉 ↦ ( 𝐶 ( .r𝑀 ) ( 𝐴𝑣 ) ) ) supp ( 0g𝑀 ) ) ∈ Fin ) ) )
14 3 7 13 mpbir2and ( ( ( 𝑀 ∈ Ring ∧ 𝑉𝑋𝐶𝑅 ) ∧ 𝐴 ∈ ( 𝑅m 𝑉 ) ∧ 𝐴 finSupp ( 0g𝑀 ) ) → ( 𝑣𝑉 ↦ ( 𝐶 ( .r𝑀 ) ( 𝐴𝑣 ) ) ) finSupp ( 0g𝑀 ) )