Description: Difference law for Cartesian products. (Contributed by Thierry Arnoux, 24-Jul-2023)
| Ref | Expression | ||
|---|---|---|---|
| Assertion | difxp2ss | ⊢ ( 𝐴 × ( 𝐵 ∖ 𝐶 ) ) ⊆ ( 𝐴 × 𝐵 ) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | difxp2 | ⊢ ( 𝐴 × ( 𝐵 ∖ 𝐶 ) ) = ( ( 𝐴 × 𝐵 ) ∖ ( 𝐴 × 𝐶 ) ) | |
| 2 | difss | ⊢ ( ( 𝐴 × 𝐵 ) ∖ ( 𝐴 × 𝐶 ) ) ⊆ ( 𝐴 × 𝐵 ) | |
| 3 | 1 2 | eqsstri | ⊢ ( 𝐴 × ( 𝐵 ∖ 𝐶 ) ) ⊆ ( 𝐴 × 𝐵 ) |