a) lim_{x→1}f(x)\n3\nb) lim_{x→4}f(x)

Explanation:

Step1: Recall limit definition

The limit as $x$ approaches a value is the value the function approaches as $x$ gets closer to that value.

Step2: Analyze $\lim_{x\rightarrow1}f(x)$

As $x$ approaches 1 from both the left - hand side and the right - hand side, the function $y = f(x)$ approaches 3. So $\lim_{x\rightarrow1}f(x)=3$.

Step3: Analyze $\lim_{x\rightarrow4}f(x)$

As $x$ approaches 4 from the left - hand side, $y = f(x)$ approaches 2, and as $x$ approaches 4 from the right - hand side, $y = f(x)$ approaches 2. So $\lim_{x\rightarrow4}f(x)=2$.

Answer:

a) 3 b) 2