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 ) ) |
| 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 ) ) |