![]() |
Metamath Proof Explorer |
< Previous
Next >
Nearby theorems |
|
Mirrors > Home > MPE Home > Th. List > df-iin | Structured version Visualization version GIF version |
Description: Define indexed intersection. Definition of [Stoll] p. 45. See the remarks for its sibling operation of indexed union df-iun 5000. An alternate definition tying indexed intersection to ordinary intersection is dfiin2 5038. Theorem intiin 5063 provides a definition of ordinary intersection in terms of indexed intersection. (Contributed by NM, 27-Jun-1998.) |
Ref | Expression |
---|---|
df-iin | ⊢ ∩ 𝑥 ∈ 𝐴 𝐵 = {𝑦 ∣ ∀𝑥 ∈ 𝐴 𝑦 ∈ 𝐵} |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | vx | . . 3 setvar 𝑥 | |
2 | cA | . . 3 class 𝐴 | |
3 | cB | . . 3 class 𝐵 | |
4 | 1, 2, 3 | ciin 4999 | . 2 class ∩ 𝑥 ∈ 𝐴 𝐵 |
5 | vy | . . . . . 6 setvar 𝑦 | |
6 | 5 | cv 1541 | . . . . 5 class 𝑦 |
7 | 6, 3 | wcel 2107 | . . . 4 wff 𝑦 ∈ 𝐵 |
8 | 7, 1, 2 | wral 3062 | . . 3 wff ∀𝑥 ∈ 𝐴 𝑦 ∈ 𝐵 |
9 | 8, 5 | cab 2710 | . 2 class {𝑦 ∣ ∀𝑥 ∈ 𝐴 𝑦 ∈ 𝐵} |
10 | 4, 9 | wceq 1542 | 1 wff ∩ 𝑥 ∈ 𝐴 𝐵 = {𝑦 ∣ ∀𝑥 ∈ 𝐴 𝑦 ∈ 𝐵} |
Colors of variables: wff setvar class |
This definition is referenced by: eliin 5003 iineq1 5015 iineq2 5018 nfiin 5029 nfiing 5031 nfii1 5033 dfiin2g 5036 cbviin 5041 cbviing 5043 intiin 5063 0iin 5068 viin 5069 iinxsng 5092 iinxprg 5093 iinuni 5102 iinabrex 31800 iineq12f 37032 |
Copyright terms: Public domain | W3C validator |