3. What is the domain of the following real valued function?
$$f ( x ) = \log _ { 2 } \left( x ^ { 2 } - 5 x + 6 \right)$$
(a) $( - \infty , 2 )$
(b) $( 3 , \infty )$
(c) $( - \infty , 2 ) \cup ( 3 , \infty )$
(d) $( - \infty , \infty )$
3. What is the domain of the following real valued function?

$$f ( x ) = \log _ { 2 } \left( x ^ { 2 } - 5 x + 6 \right)$$

(a) $( - \infty , 2 )$\\
(b) $( 3 , \infty )$\\
(c) $( - \infty , 2 ) \cup ( 3 , \infty )$\\
(d) $( - \infty , \infty )$\\