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Description: Operation value of the empty set. (Contributed by AV, 15-May-2021)
| Ref | Expression | ||
|---|---|---|---|
| Assertion | 0ov | ⊢ ( 𝐴 ∅ 𝐵 ) = ∅ |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | df-ov | ⊢ ( 𝐴 ∅ 𝐵 ) = ( ∅ ‘ 〈 𝐴 , 𝐵 〉 ) | |
| 2 | 0fv | ⊢ ( ∅ ‘ 〈 𝐴 , 𝐵 〉 ) = ∅ | |
| 3 | 1 2 | eqtri | ⊢ ( 𝐴 ∅ 𝐵 ) = ∅ |