1. **State the problem:** We need to find the points where the piecewise function
$$f(x) = \begin{cases} x + 8 & x < 0 \\ e^x & 0 \leq x \leq 1 \\ 2 - x & x > 1 \end{cases}$$
is discontinuous, and determine if it is continuous from the right, left, or neither at those points.
2. **Identify potential discontinuities:** The function changes definition at $x=0$ and $x=1$, so check continuity at these points.
3. **Check continuity at $x=0$:**
- Left-hand limit: $\lim_{x \to 0^-} f(x) = \lim_{x \to 0^-} (x+8) = 0 + 8 = 8$
- Right-hand limit: $\lim_{x \to 0^+} f(x) = \lim_{x \to 0^+} e^x = e^0 = 1$
- Function value: $f(0) = e^0 = 1$
Since left limit $8 \neq$ right limit $1$, the limit does not exist at $x=0$, so $f$ is discontinuous at $x=0$.
Check one-sided continuity:
- Continuous from the right if $\lim_{x \to 0^+} f(x) = f(0)$: here $1=1$, so yes.
- Continuous from the left if $\lim_{x \to 0^-} f(x) = f(0)$: here $8 \neq 1$, so no.
4. **Check continuity at $x=1$:**
- Left-hand limit: $\lim_{x \to 1^-} f(x) = \lim_{x \to 1^-} e^x = e^1 = e$
- Right-hand limit: $\lim_{x \to 1^+} f(x) = \lim_{x \to 1^+} (2 - x) = 2 - 1 = 1$
- Function value: $f(1) = e^1 = e$
Since left limit $e \neq$ right limit $1$, the limit does not exist at $x=1$, so $f$ is discontinuous at $x=1$.
Check one-sided continuity:
- Continuous from the left if $\lim_{x \to 1^-} f(x) = f(1)$: here $e = e$, so yes.
- Continuous from the right if $\lim_{x \to 1^+} f(x) = f(1)$: here $1 \neq e$, so no.
5. **Summary:**
- At $x=0$, $f$ is discontinuous, continuous from the right only.
- At $x=1$, $f$ is discontinuous, continuous from the left only.
6. **Graph description:**
- For $x<0$, $f(x) = x+8$ is a line with slope 1 and y-intercept 8.
- For $0 \leq x \leq 1$, $f(x) = e^x$ is an increasing exponential curve from $1$ to $e \approx 2.718$.
- For $x>1$, $f(x) = 2 - x$ is a line with slope $-1$ starting at $1$ when $x=1$ and decreasing.
This matches the given graph description with jumps at $x=0$ and $x=1$.
Final answers:
- Discontinuities at $x=0$ and $x=1$.
- At $x=0$, continuous from the right only.
- At $x=1$, continuous from the left only.
Discontinuity Points 6Bd986
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