[tex] \it 15\ \vdots\ x \Rightarrow x \in \{\pm1,\ \pm3,\ \pm5, \ \pm15\} \Rightarrow A = \{-15,\ -5,\ -3,\ -1,\ 1,\ 3,\ 5,\ 15\}\\ \\ |x <3 | \Rightarrow -3<x<3 \Rightarrow B = \{-2,\ \ -1,\ \ 0,\ \ 1,\ \ 2\}\\ \\ x+2|3 \Rightarrow x+2\in \{-3,\ -1, \ 1,\ 3\}|_{-2} \Rightarrow C=\{-5,\ \ -3,\ \ -1,\ \ 1 \} [/tex]
[tex] \it A\cap B = \{-1,\ \ 1\}\\ \\ B\cup C =\{-5,\ \ -3,\ \ -2,\ \ -1,\ \ 0,\ \ 1, \ \ 2 \}\\ \\ C \backslash B =\{-5,\ \ -3\} [/tex]