Description: Existence of a difference. (Contributed by NM, 26-May-1998)
Ref | Expression | ||
---|---|---|---|
Assertion | difexg | ⊢ ( 𝐴 ∈ 𝑉 → ( 𝐴 ∖ 𝐵 ) ∈ V ) |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | difss | ⊢ ( 𝐴 ∖ 𝐵 ) ⊆ 𝐴 | |
2 | ssexg | ⊢ ( ( ( 𝐴 ∖ 𝐵 ) ⊆ 𝐴 ∧ 𝐴 ∈ 𝑉 ) → ( 𝐴 ∖ 𝐵 ) ∈ V ) | |
3 | 1 2 | mpan | ⊢ ( 𝐴 ∈ 𝑉 → ( 𝐴 ∖ 𝐵 ) ∈ V ) |