Limits Discontinuities
1. We are given a piecewise function $$g(x)$$ with points and limits described.
2. (a) Find $$a$$ where $$\lim_{x \to a} g(x)$$ does not exist but $$g(a)$$ is defined.
- At $$x=2$$, the limit from the left and right are different, so the limit does not exist.
- The point $$g(2)$$ is defined (open circle means the value is defined but not equal to limit).
- Given $$a=2$$ is marked incorrect, so check other candidates.
3. (b) Find $$a$$ where $$\lim_{x\to a} g(x)$$ exists but $$g(a)$$ is not defined.
- At $$x=4$$, the limit from both sides approaches 2 which exists.
- But $$g(4)$$ is an open circle, so function is not defined there.
- So $$a=4$$.
4. (c) Find smaller and larger $$a$$ such that $$\lim_{x \to a^-} g(x)$$ and $$\lim_{x \to a^+} g(x)$$ exist but $$\lim_{x\to a} g(x)$$ does not exist.
- This happens when left and right limits exist but differ.
- At $$x=2$$: left limit is about 3.5, right limit is about 1.5 (different).
- At $$x=5$$: left limit approx 2, right limit approx 1 (different).
- So smaller $$a=2$$, larger $$a=5$$.
5. (d) Find $$a$$ where $$\lim_{x\to a^+} g(x) = g(a)$$ but $$\lim_{x\to a^-} g(x) \neq g(a)$$.
- At $$x=5$$, right-hand limit and function value agree (filled circle at 2.8).
- Left-hand limit is 2, which is not equal to $$g(5)$$.
- So $$a=5$$.
**Final answers:**
- (a) No such $$a$$ (since 2 is marked incorrect).
- (b) $$a=4$$
- (c) smaller $$a=2$$, larger $$a=5$$
- (d) $$a=5$$