theorem Set.mem_sdiff_of_memtheorem Set.mem_sdiff_of_mem: ∀ {α : Type u} {s t : Set α} {x : α}, x ∈ s → ¬x ∈ t → x ∈ s \ t
Published by @sam · Jul 21, 2026
View source in zpg9xh52
zpg9xh52
Definitional, with no premises to accept.
Set.mem_sdiff_of_mem
definitional fact