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Mirrors > Home > NFE Home > Th. List > imakeq1 | GIF version |
Description: Equality theorem for Kuratowski image. (Contributed by SF, 12-Jan-2015.) |
Ref | Expression |
---|---|
imakeq1 | ⊢ (A = B → (A “k C) = (B “k C)) |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | eleq2 2414 | . . . 4 ⊢ (A = B → (⟪y, x⟫ ∈ A ↔ ⟪y, x⟫ ∈ B)) | |
2 | 1 | rexbidv 2636 | . . 3 ⊢ (A = B → (∃y ∈ C ⟪y, x⟫ ∈ A ↔ ∃y ∈ C ⟪y, x⟫ ∈ B)) |
3 | 2 | abbidv 2468 | . 2 ⊢ (A = B → {x ∣ ∃y ∈ C ⟪y, x⟫ ∈ A} = {x ∣ ∃y ∈ C ⟪y, x⟫ ∈ B}) |
4 | df-imak 4190 | . 2 ⊢ (A “k C) = {x ∣ ∃y ∈ C ⟪y, x⟫ ∈ A} | |
5 | df-imak 4190 | . 2 ⊢ (B “k C) = {x ∣ ∃y ∈ C ⟪y, x⟫ ∈ B} | |
6 | 3, 4, 5 | 3eqtr4g 2410 | 1 ⊢ (A = B → (A “k C) = (B “k C)) |
Colors of variables: wff setvar class |
Syntax hints: → wi 4 = wceq 1642 ∈ wcel 1710 {cab 2339 ∃wrex 2616 ⟪copk 4058 “k cimak 4180 |
This theorem was proved from axioms: ax-mp 5 ax-1 6 ax-2 7 ax-3 8 ax-gen 1546 ax-5 1557 ax-17 1616 ax-9 1654 ax-8 1675 ax-6 1729 ax-7 1734 ax-11 1746 ax-12 1925 ax-ext 2334 |
This theorem depends on definitions: df-bi 177 df-an 360 df-tru 1319 df-ex 1542 df-nf 1545 df-sb 1649 df-clab 2340 df-cleq 2346 df-clel 2349 df-rex 2621 df-imak 4190 |
This theorem is referenced by: imakeq1i 4227 imakeq1d 4229 |
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