Metamath Proof Explorer


Theorem ressds

Description: dist is unaffected by restriction. (Contributed by Mario Carneiro, 26-Aug-2015)

Ref Expression
Hypotheses ressds.1 ⊢ 𝐻 = ( 𝐺 ↾s 𝐴 )
ressds.2 ⊢ 𝐷 = ( dist ‘ 𝐺 )
Assertion ressds ( 𝐴 ∈ 𝑉 → 𝐷 = ( dist ‘ 𝐻 ) )

Proof

Step Hyp Ref Expression
1 ressds.1 ⊢ 𝐻 = ( 𝐺 ↾s 𝐴 )
2 ressds.2 ⊢ 𝐷 = ( dist ‘ 𝐺 )
3 dsid ⊢ dist = Slot ( dist ‘ ndx )
4 dsndxnbasendx ⊢ ( dist ‘ ndx ) ≠ ( Base ‘ ndx )
5 1 2 3 4 resseqnbas ⊢ ( 𝐴 ∈ 𝑉 → 𝐷 = ( dist ‘ 𝐻 ) )