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Description: Two ways to express the intersection of a range Cartesian product with a Cartesian product. (Contributed by Peter Mazsa, 10-Apr-2020)
| Ref | Expression | ||
|---|---|---|---|
| Assertion | inxpxrn | ⊢ ( ( 𝑅 ∩ ( 𝐴 × 𝐵 ) ) ⋉ ( 𝑆 ∩ ( 𝐴 × 𝐶 ) ) ) = ( ( 𝑅 ⋉ 𝑆 ) ∩ ( 𝐴 × ( 𝐵 × 𝐶 ) ) ) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | xrnrel | ⊢ Rel ( ( 𝑅 ∩ ( 𝐴 × 𝐵 ) ) ⋉ ( 𝑆 ∩ ( 𝐴 × 𝐶 ) ) ) | |
| 2 | relinxp | ⊢ Rel ( ( 𝑅 ⋉ 𝑆 ) ∩ ( 𝐴 × ( 𝐵 × 𝐶 ) ) ) | |
| 3 | brxrn2 | ⊢ ( 𝑢 ∈ V → ( 𝑢 ( 𝑅 ⋉ 𝑆 ) 𝑥 ↔ ∃ 𝑦 ∃ 𝑧 ( 𝑥 = 〈 𝑦 , 𝑧 〉 ∧ 𝑢 𝑅 𝑦 ∧ 𝑢 𝑆 𝑧 ) ) ) | |
| 4 | 3 | elv | ⊢ ( 𝑢 ( 𝑅 ⋉ 𝑆 ) 𝑥 ↔ ∃ 𝑦 ∃ 𝑧 ( 𝑥 = 〈 𝑦 , 𝑧 〉 ∧ 𝑢 𝑅 𝑦 ∧ 𝑢 𝑆 𝑧 ) ) |
| 5 | 4 | anbi2i | ⊢ ( ( 𝑢 ∈ 𝐴 ∧ 𝑢 ( 𝑅 ⋉ 𝑆 ) 𝑥 ) ↔ ( 𝑢 ∈ 𝐴 ∧ ∃ 𝑦 ∃ 𝑧 ( 𝑥 = 〈 𝑦 , 𝑧 〉 ∧ 𝑢 𝑅 𝑦 ∧ 𝑢 𝑆 𝑧 ) ) ) |
| 6 | 5 | anbi2i | ⊢ ( ( 𝑥 ∈ ( 𝐵 × 𝐶 ) ∧ ( 𝑢 ∈ 𝐴 ∧ 𝑢 ( 𝑅 ⋉ 𝑆 ) 𝑥 ) ) ↔ ( 𝑥 ∈ ( 𝐵 × 𝐶 ) ∧ ( 𝑢 ∈ 𝐴 ∧ ∃ 𝑦 ∃ 𝑧 ( 𝑥 = 〈 𝑦 , 𝑧 〉 ∧ 𝑢 𝑅 𝑦 ∧ 𝑢 𝑆 𝑧 ) ) ) ) |
| 7 | xrninxp2 | ⊢ ( ( 𝑅 ⋉ 𝑆 ) ∩ ( 𝐴 × ( 𝐵 × 𝐶 ) ) ) = { 〈 𝑢 , 𝑥 〉 ∣ ( 𝑥 ∈ ( 𝐵 × 𝐶 ) ∧ ( 𝑢 ∈ 𝐴 ∧ 𝑢 ( 𝑅 ⋉ 𝑆 ) 𝑥 ) ) } | |
| 8 | 7 | brabidgaw | ⊢ ( 𝑢 ( ( 𝑅 ⋉ 𝑆 ) ∩ ( 𝐴 × ( 𝐵 × 𝐶 ) ) ) 𝑥 ↔ ( 𝑥 ∈ ( 𝐵 × 𝐶 ) ∧ ( 𝑢 ∈ 𝐴 ∧ 𝑢 ( 𝑅 ⋉ 𝑆 ) 𝑥 ) ) ) |
| 9 | brxrn2 | ⊢ ( 𝑢 ∈ V → ( 𝑢 ( ( 𝑅 ∩ ( 𝐴 × 𝐵 ) ) ⋉ ( 𝑆 ∩ ( 𝐴 × 𝐶 ) ) ) 𝑥 ↔ ∃ 𝑦 ∃ 𝑧 ( 𝑥 = 〈 𝑦 , 𝑧 〉 ∧ 𝑢 ( 𝑅 ∩ ( 𝐴 × 𝐵 ) ) 𝑦 ∧ 𝑢 ( 𝑆 ∩ ( 𝐴 × 𝐶 ) ) 𝑧 ) ) ) | |
| 10 | 9 | elv | ⊢ ( 𝑢 ( ( 𝑅 ∩ ( 𝐴 × 𝐵 ) ) ⋉ ( 𝑆 ∩ ( 𝐴 × 𝐶 ) ) ) 𝑥 ↔ ∃ 𝑦 ∃ 𝑧 ( 𝑥 = 〈 𝑦 , 𝑧 〉 ∧ 𝑢 ( 𝑅 ∩ ( 𝐴 × 𝐵 ) ) 𝑦 ∧ 𝑢 ( 𝑆 ∩ ( 𝐴 × 𝐶 ) ) 𝑧 ) ) |
| 11 | 3anass | ⊢ ( ( 𝑥 = 〈 𝑦 , 𝑧 〉 ∧ 𝑢 ( 𝑅 ∩ ( 𝐴 × 𝐵 ) ) 𝑦 ∧ 𝑢 ( 𝑆 ∩ ( 𝐴 × 𝐶 ) ) 𝑧 ) ↔ ( 𝑥 = 〈 𝑦 , 𝑧 〉 ∧ ( 𝑢 ( 𝑅 ∩ ( 𝐴 × 𝐵 ) ) 𝑦 ∧ 𝑢 ( 𝑆 ∩ ( 𝐴 × 𝐶 ) ) 𝑧 ) ) ) | |
| 12 | 11 | 2exbii | ⊢ ( ∃ 𝑦 ∃ 𝑧 ( 𝑥 = 〈 𝑦 , 𝑧 〉 ∧ 𝑢 ( 𝑅 ∩ ( 𝐴 × 𝐵 ) ) 𝑦 ∧ 𝑢 ( 𝑆 ∩ ( 𝐴 × 𝐶 ) ) 𝑧 ) ↔ ∃ 𝑦 ∃ 𝑧 ( 𝑥 = 〈 𝑦 , 𝑧 〉 ∧ ( 𝑢 ( 𝑅 ∩ ( 𝐴 × 𝐵 ) ) 𝑦 ∧ 𝑢 ( 𝑆 ∩ ( 𝐴 × 𝐶 ) ) 𝑧 ) ) ) |
| 13 | brinxp2 | ⊢ ( 𝑢 ( 𝑅 ∩ ( 𝐴 × 𝐵 ) ) 𝑦 ↔ ( ( 𝑢 ∈ 𝐴 ∧ 𝑦 ∈ 𝐵 ) ∧ 𝑢 𝑅 𝑦 ) ) | |
| 14 | brinxp2 | ⊢ ( 𝑢 ( 𝑆 ∩ ( 𝐴 × 𝐶 ) ) 𝑧 ↔ ( ( 𝑢 ∈ 𝐴 ∧ 𝑧 ∈ 𝐶 ) ∧ 𝑢 𝑆 𝑧 ) ) | |
| 15 | 13 14 | anbi12i | ⊢ ( ( 𝑢 ( 𝑅 ∩ ( 𝐴 × 𝐵 ) ) 𝑦 ∧ 𝑢 ( 𝑆 ∩ ( 𝐴 × 𝐶 ) ) 𝑧 ) ↔ ( ( ( 𝑢 ∈ 𝐴 ∧ 𝑦 ∈ 𝐵 ) ∧ 𝑢 𝑅 𝑦 ) ∧ ( ( 𝑢 ∈ 𝐴 ∧ 𝑧 ∈ 𝐶 ) ∧ 𝑢 𝑆 𝑧 ) ) ) |
| 16 | anan | ⊢ ( ( ( ( 𝑢 ∈ 𝐴 ∧ 𝑦 ∈ 𝐵 ) ∧ 𝑢 𝑅 𝑦 ) ∧ ( ( 𝑢 ∈ 𝐴 ∧ 𝑧 ∈ 𝐶 ) ∧ 𝑢 𝑆 𝑧 ) ) ↔ ( ( 𝑦 ∈ 𝐵 ∧ 𝑧 ∈ 𝐶 ) ∧ ( 𝑢 ∈ 𝐴 ∧ ( 𝑢 𝑅 𝑦 ∧ 𝑢 𝑆 𝑧 ) ) ) ) | |
| 17 | 15 16 | bitri | ⊢ ( ( 𝑢 ( 𝑅 ∩ ( 𝐴 × 𝐵 ) ) 𝑦 ∧ 𝑢 ( 𝑆 ∩ ( 𝐴 × 𝐶 ) ) 𝑧 ) ↔ ( ( 𝑦 ∈ 𝐵 ∧ 𝑧 ∈ 𝐶 ) ∧ ( 𝑢 ∈ 𝐴 ∧ ( 𝑢 𝑅 𝑦 ∧ 𝑢 𝑆 𝑧 ) ) ) ) |
| 18 | 17 | anbi2i | ⊢ ( ( 𝑥 = 〈 𝑦 , 𝑧 〉 ∧ ( 𝑢 ( 𝑅 ∩ ( 𝐴 × 𝐵 ) ) 𝑦 ∧ 𝑢 ( 𝑆 ∩ ( 𝐴 × 𝐶 ) ) 𝑧 ) ) ↔ ( 𝑥 = 〈 𝑦 , 𝑧 〉 ∧ ( ( 𝑦 ∈ 𝐵 ∧ 𝑧 ∈ 𝐶 ) ∧ ( 𝑢 ∈ 𝐴 ∧ ( 𝑢 𝑅 𝑦 ∧ 𝑢 𝑆 𝑧 ) ) ) ) ) |
| 19 | anass | ⊢ ( ( ( 𝑥 = 〈 𝑦 , 𝑧 〉 ∧ ( 𝑦 ∈ 𝐵 ∧ 𝑧 ∈ 𝐶 ) ) ∧ ( 𝑢 ∈ 𝐴 ∧ ( 𝑢 𝑅 𝑦 ∧ 𝑢 𝑆 𝑧 ) ) ) ↔ ( 𝑥 = 〈 𝑦 , 𝑧 〉 ∧ ( ( 𝑦 ∈ 𝐵 ∧ 𝑧 ∈ 𝐶 ) ∧ ( 𝑢 ∈ 𝐴 ∧ ( 𝑢 𝑅 𝑦 ∧ 𝑢 𝑆 𝑧 ) ) ) ) ) | |
| 20 | eqelb | ⊢ ( ( 𝑥 = 〈 𝑦 , 𝑧 〉 ∧ 𝑥 ∈ ( 𝐵 × 𝐶 ) ) ↔ ( 𝑥 = 〈 𝑦 , 𝑧 〉 ∧ 〈 𝑦 , 𝑧 〉 ∈ ( 𝐵 × 𝐶 ) ) ) | |
| 21 | opelxp | ⊢ ( 〈 𝑦 , 𝑧 〉 ∈ ( 𝐵 × 𝐶 ) ↔ ( 𝑦 ∈ 𝐵 ∧ 𝑧 ∈ 𝐶 ) ) | |
| 22 | 21 | anbi2i | ⊢ ( ( 𝑥 = 〈 𝑦 , 𝑧 〉 ∧ 〈 𝑦 , 𝑧 〉 ∈ ( 𝐵 × 𝐶 ) ) ↔ ( 𝑥 = 〈 𝑦 , 𝑧 〉 ∧ ( 𝑦 ∈ 𝐵 ∧ 𝑧 ∈ 𝐶 ) ) ) |
| 23 | 20 22 | bitr2i | ⊢ ( ( 𝑥 = 〈 𝑦 , 𝑧 〉 ∧ ( 𝑦 ∈ 𝐵 ∧ 𝑧 ∈ 𝐶 ) ) ↔ ( 𝑥 = 〈 𝑦 , 𝑧 〉 ∧ 𝑥 ∈ ( 𝐵 × 𝐶 ) ) ) |
| 24 | 23 | anbi1i | ⊢ ( ( ( 𝑥 = 〈 𝑦 , 𝑧 〉 ∧ ( 𝑦 ∈ 𝐵 ∧ 𝑧 ∈ 𝐶 ) ) ∧ ( 𝑢 ∈ 𝐴 ∧ ( 𝑢 𝑅 𝑦 ∧ 𝑢 𝑆 𝑧 ) ) ) ↔ ( ( 𝑥 = 〈 𝑦 , 𝑧 〉 ∧ 𝑥 ∈ ( 𝐵 × 𝐶 ) ) ∧ ( 𝑢 ∈ 𝐴 ∧ ( 𝑢 𝑅 𝑦 ∧ 𝑢 𝑆 𝑧 ) ) ) ) |
| 25 | 18 19 24 | 3bitr2i | ⊢ ( ( 𝑥 = 〈 𝑦 , 𝑧 〉 ∧ ( 𝑢 ( 𝑅 ∩ ( 𝐴 × 𝐵 ) ) 𝑦 ∧ 𝑢 ( 𝑆 ∩ ( 𝐴 × 𝐶 ) ) 𝑧 ) ) ↔ ( ( 𝑥 = 〈 𝑦 , 𝑧 〉 ∧ 𝑥 ∈ ( 𝐵 × 𝐶 ) ) ∧ ( 𝑢 ∈ 𝐴 ∧ ( 𝑢 𝑅 𝑦 ∧ 𝑢 𝑆 𝑧 ) ) ) ) |
| 26 | ancom | ⊢ ( ( 𝑥 = 〈 𝑦 , 𝑧 〉 ∧ 𝑥 ∈ ( 𝐵 × 𝐶 ) ) ↔ ( 𝑥 ∈ ( 𝐵 × 𝐶 ) ∧ 𝑥 = 〈 𝑦 , 𝑧 〉 ) ) | |
| 27 | 26 | anbi1i | ⊢ ( ( ( 𝑥 = 〈 𝑦 , 𝑧 〉 ∧ 𝑥 ∈ ( 𝐵 × 𝐶 ) ) ∧ ( 𝑢 ∈ 𝐴 ∧ ( 𝑢 𝑅 𝑦 ∧ 𝑢 𝑆 𝑧 ) ) ) ↔ ( ( 𝑥 ∈ ( 𝐵 × 𝐶 ) ∧ 𝑥 = 〈 𝑦 , 𝑧 〉 ) ∧ ( 𝑢 ∈ 𝐴 ∧ ( 𝑢 𝑅 𝑦 ∧ 𝑢 𝑆 𝑧 ) ) ) ) |
| 28 | anass | ⊢ ( ( ( 𝑥 ∈ ( 𝐵 × 𝐶 ) ∧ 𝑥 = 〈 𝑦 , 𝑧 〉 ) ∧ ( 𝑢 ∈ 𝐴 ∧ ( 𝑢 𝑅 𝑦 ∧ 𝑢 𝑆 𝑧 ) ) ) ↔ ( 𝑥 ∈ ( 𝐵 × 𝐶 ) ∧ ( 𝑥 = 〈 𝑦 , 𝑧 〉 ∧ ( 𝑢 ∈ 𝐴 ∧ ( 𝑢 𝑅 𝑦 ∧ 𝑢 𝑆 𝑧 ) ) ) ) ) | |
| 29 | 25 27 28 | 3bitri | ⊢ ( ( 𝑥 = 〈 𝑦 , 𝑧 〉 ∧ ( 𝑢 ( 𝑅 ∩ ( 𝐴 × 𝐵 ) ) 𝑦 ∧ 𝑢 ( 𝑆 ∩ ( 𝐴 × 𝐶 ) ) 𝑧 ) ) ↔ ( 𝑥 ∈ ( 𝐵 × 𝐶 ) ∧ ( 𝑥 = 〈 𝑦 , 𝑧 〉 ∧ ( 𝑢 ∈ 𝐴 ∧ ( 𝑢 𝑅 𝑦 ∧ 𝑢 𝑆 𝑧 ) ) ) ) ) |
| 30 | an12 | ⊢ ( ( 𝑥 = 〈 𝑦 , 𝑧 〉 ∧ ( 𝑢 ∈ 𝐴 ∧ ( 𝑢 𝑅 𝑦 ∧ 𝑢 𝑆 𝑧 ) ) ) ↔ ( 𝑢 ∈ 𝐴 ∧ ( 𝑥 = 〈 𝑦 , 𝑧 〉 ∧ ( 𝑢 𝑅 𝑦 ∧ 𝑢 𝑆 𝑧 ) ) ) ) | |
| 31 | 3anass | ⊢ ( ( 𝑥 = 〈 𝑦 , 𝑧 〉 ∧ 𝑢 𝑅 𝑦 ∧ 𝑢 𝑆 𝑧 ) ↔ ( 𝑥 = 〈 𝑦 , 𝑧 〉 ∧ ( 𝑢 𝑅 𝑦 ∧ 𝑢 𝑆 𝑧 ) ) ) | |
| 32 | 31 | anbi2i | ⊢ ( ( 𝑢 ∈ 𝐴 ∧ ( 𝑥 = 〈 𝑦 , 𝑧 〉 ∧ 𝑢 𝑅 𝑦 ∧ 𝑢 𝑆 𝑧 ) ) ↔ ( 𝑢 ∈ 𝐴 ∧ ( 𝑥 = 〈 𝑦 , 𝑧 〉 ∧ ( 𝑢 𝑅 𝑦 ∧ 𝑢 𝑆 𝑧 ) ) ) ) |
| 33 | 30 32 | bitr4i | ⊢ ( ( 𝑥 = 〈 𝑦 , 𝑧 〉 ∧ ( 𝑢 ∈ 𝐴 ∧ ( 𝑢 𝑅 𝑦 ∧ 𝑢 𝑆 𝑧 ) ) ) ↔ ( 𝑢 ∈ 𝐴 ∧ ( 𝑥 = 〈 𝑦 , 𝑧 〉 ∧ 𝑢 𝑅 𝑦 ∧ 𝑢 𝑆 𝑧 ) ) ) |
| 34 | 33 | anbi2i | ⊢ ( ( 𝑥 ∈ ( 𝐵 × 𝐶 ) ∧ ( 𝑥 = 〈 𝑦 , 𝑧 〉 ∧ ( 𝑢 ∈ 𝐴 ∧ ( 𝑢 𝑅 𝑦 ∧ 𝑢 𝑆 𝑧 ) ) ) ) ↔ ( 𝑥 ∈ ( 𝐵 × 𝐶 ) ∧ ( 𝑢 ∈ 𝐴 ∧ ( 𝑥 = 〈 𝑦 , 𝑧 〉 ∧ 𝑢 𝑅 𝑦 ∧ 𝑢 𝑆 𝑧 ) ) ) ) |
| 35 | 29 34 | bitri | ⊢ ( ( 𝑥 = 〈 𝑦 , 𝑧 〉 ∧ ( 𝑢 ( 𝑅 ∩ ( 𝐴 × 𝐵 ) ) 𝑦 ∧ 𝑢 ( 𝑆 ∩ ( 𝐴 × 𝐶 ) ) 𝑧 ) ) ↔ ( 𝑥 ∈ ( 𝐵 × 𝐶 ) ∧ ( 𝑢 ∈ 𝐴 ∧ ( 𝑥 = 〈 𝑦 , 𝑧 〉 ∧ 𝑢 𝑅 𝑦 ∧ 𝑢 𝑆 𝑧 ) ) ) ) |
| 36 | 35 | 2exbii | ⊢ ( ∃ 𝑦 ∃ 𝑧 ( 𝑥 = 〈 𝑦 , 𝑧 〉 ∧ ( 𝑢 ( 𝑅 ∩ ( 𝐴 × 𝐵 ) ) 𝑦 ∧ 𝑢 ( 𝑆 ∩ ( 𝐴 × 𝐶 ) ) 𝑧 ) ) ↔ ∃ 𝑦 ∃ 𝑧 ( 𝑥 ∈ ( 𝐵 × 𝐶 ) ∧ ( 𝑢 ∈ 𝐴 ∧ ( 𝑥 = 〈 𝑦 , 𝑧 〉 ∧ 𝑢 𝑅 𝑦 ∧ 𝑢 𝑆 𝑧 ) ) ) ) |
| 37 | 19.42vv | ⊢ ( ∃ 𝑦 ∃ 𝑧 ( 𝑥 ∈ ( 𝐵 × 𝐶 ) ∧ ( 𝑢 ∈ 𝐴 ∧ ( 𝑥 = 〈 𝑦 , 𝑧 〉 ∧ 𝑢 𝑅 𝑦 ∧ 𝑢 𝑆 𝑧 ) ) ) ↔ ( 𝑥 ∈ ( 𝐵 × 𝐶 ) ∧ ∃ 𝑦 ∃ 𝑧 ( 𝑢 ∈ 𝐴 ∧ ( 𝑥 = 〈 𝑦 , 𝑧 〉 ∧ 𝑢 𝑅 𝑦 ∧ 𝑢 𝑆 𝑧 ) ) ) ) | |
| 38 | 19.42vv | ⊢ ( ∃ 𝑦 ∃ 𝑧 ( 𝑢 ∈ 𝐴 ∧ ( 𝑥 = 〈 𝑦 , 𝑧 〉 ∧ 𝑢 𝑅 𝑦 ∧ 𝑢 𝑆 𝑧 ) ) ↔ ( 𝑢 ∈ 𝐴 ∧ ∃ 𝑦 ∃ 𝑧 ( 𝑥 = 〈 𝑦 , 𝑧 〉 ∧ 𝑢 𝑅 𝑦 ∧ 𝑢 𝑆 𝑧 ) ) ) | |
| 39 | 38 | anbi2i | ⊢ ( ( 𝑥 ∈ ( 𝐵 × 𝐶 ) ∧ ∃ 𝑦 ∃ 𝑧 ( 𝑢 ∈ 𝐴 ∧ ( 𝑥 = 〈 𝑦 , 𝑧 〉 ∧ 𝑢 𝑅 𝑦 ∧ 𝑢 𝑆 𝑧 ) ) ) ↔ ( 𝑥 ∈ ( 𝐵 × 𝐶 ) ∧ ( 𝑢 ∈ 𝐴 ∧ ∃ 𝑦 ∃ 𝑧 ( 𝑥 = 〈 𝑦 , 𝑧 〉 ∧ 𝑢 𝑅 𝑦 ∧ 𝑢 𝑆 𝑧 ) ) ) ) |
| 40 | 36 37 39 | 3bitri | ⊢ ( ∃ 𝑦 ∃ 𝑧 ( 𝑥 = 〈 𝑦 , 𝑧 〉 ∧ ( 𝑢 ( 𝑅 ∩ ( 𝐴 × 𝐵 ) ) 𝑦 ∧ 𝑢 ( 𝑆 ∩ ( 𝐴 × 𝐶 ) ) 𝑧 ) ) ↔ ( 𝑥 ∈ ( 𝐵 × 𝐶 ) ∧ ( 𝑢 ∈ 𝐴 ∧ ∃ 𝑦 ∃ 𝑧 ( 𝑥 = 〈 𝑦 , 𝑧 〉 ∧ 𝑢 𝑅 𝑦 ∧ 𝑢 𝑆 𝑧 ) ) ) ) |
| 41 | 10 12 40 | 3bitri | ⊢ ( 𝑢 ( ( 𝑅 ∩ ( 𝐴 × 𝐵 ) ) ⋉ ( 𝑆 ∩ ( 𝐴 × 𝐶 ) ) ) 𝑥 ↔ ( 𝑥 ∈ ( 𝐵 × 𝐶 ) ∧ ( 𝑢 ∈ 𝐴 ∧ ∃ 𝑦 ∃ 𝑧 ( 𝑥 = 〈 𝑦 , 𝑧 〉 ∧ 𝑢 𝑅 𝑦 ∧ 𝑢 𝑆 𝑧 ) ) ) ) |
| 42 | 6 8 41 | 3bitr4ri | ⊢ ( 𝑢 ( ( 𝑅 ∩ ( 𝐴 × 𝐵 ) ) ⋉ ( 𝑆 ∩ ( 𝐴 × 𝐶 ) ) ) 𝑥 ↔ 𝑢 ( ( 𝑅 ⋉ 𝑆 ) ∩ ( 𝐴 × ( 𝐵 × 𝐶 ) ) ) 𝑥 ) |
| 43 | 1 2 42 | eqbrriv | ⊢ ( ( 𝑅 ∩ ( 𝐴 × 𝐵 ) ) ⋉ ( 𝑆 ∩ ( 𝐴 × 𝐶 ) ) ) = ( ( 𝑅 ⋉ 𝑆 ) ∩ ( 𝐴 × ( 𝐵 × 𝐶 ) ) ) |