Respuesta :

LammettHash
If [tex]x\in A[/tex], then clearly [tex]x\in C[/tex]. We're given that [tex]B[/tex] and [tex]C[/tex] are disjoint, so no element in [tex]C[/tex] is also in [tex]B[/tex]. This means [tex]x\not\in B[/tex].