Questions: f(x) is discontinuous at x=4.
(Use a comma to separate answers as needed.)
(a) Find lim f(x) for the a-value found above. Select the correct choice below and fill in any answer boxes in your choice.
x -> a^-
A. lim x -> a^- f(x)= (Type an integer or a simplified fraction.)
B. The limit does not exist.
Transcript text: $f(x)$ is discontinuous at $x=4$.
(Use a comma to separate answers as needed.)
(a) Find $\lim f(x)$ for the a-value found above. Select the correct choice below and fill in any answer boxes in your choice.
\[
\mathrm{x} \rightarrow \mathrm{a}^{-}
\]
A. $\lim _{x \rightarrow a^{-}} f(x)=\square$ (Type an integer or a simplified fraction.)
B. The limit does not exist.
Solution
Solution Steps
To solve this problem, we need to evaluate the left-hand limit of the function \( f(x) \) as \( x \) approaches 4. This involves analyzing the behavior of \( f(x) \) as \( x \) gets closer to 4 from the left side. If the function approaches a specific value, that value is the limit; otherwise, the limit does not exist.
Step 1: Define the Function
We are given a piecewise function \( f(x) \) defined as:
\[
f(x) =
\begin{cases}
x^2 & \text{if } x < 4 \\
0 & \text{if } x \geq 4
\end{cases}
\]
Step 2: Evaluate the Left-Hand Limit
To find \( \lim_{x \to 4^{-}} f(x) \), we need to consider the value of \( f(x) \) as \( x \) approaches 4 from the left. For \( x < 4 \), \( f(x) = x^2 \).
Step 3: Calculate the Limit
We calculate the limit:
\[
\lim_{x \to 4^{-}} f(x) = \lim_{x \to 4^{-}} x^2 = 4^2 = 16
\]
Final Answer
The limit as \( x \) approaches 4 from the left is:
\[
\boxed{16}
\]
Thus, the correct choice is:
A. \( \lim_{x \to 4^{-}} f(x) = 16 \)