0 votes 0 votes Let $A,B,$ and $C$ be sets, Show that $(A \cup B) \subseteq (A \cup B \cup C),$ $(A \cap B \cap C) \subseteq (A \cap B.)$ $(A-B)-C \subseteq A-C.$ $(A-C) \cap (C-B) = \phi.$ $(B-A) \cup (C-A) = (B \cup C)- A.$ Set Theory & Algebra kenneth-rosen discrete-mathematics set-theory&algebra + – Pooja Khatri asked Apr 6, 2019 Pooja Khatri 150 views answer comment Share Follow See all 0 reply Please log in or register to add a comment.