\(\begin{array}{l}
a)\,\,x > 2 \Rightarrow A = \left\{ {x \in R|\,\,x > 2} \right\}\\
x < 16 \Rightarrow B = \left\{ {x \in R|\,\,x < 16} \right\}\\
\Rightarrow A \cap B = \left\{ {x \in R|\,\,2 < x < 16} \right\}\\
A \cup B = \left\{ {x \in R} \right\}.\\
b)\,\,2x > 8 \Leftrightarrow x > 4 \Rightarrow A = \left\{ {x \in R|\,\,\,x > 4} \right\}\\
4x > 40 \Leftrightarrow x > 10 \Rightarrow B = \left\{ {x \in R|\,\,x > 10} \right\}\\
\Rightarrow A \cap B = \left\{ {x \in R|\,\,x > 10} \right\}\\
\Rightarrow A \cup B = \left\{ {x \in R|\,\,x > 4} \right\}.
\end{array}\)
