One-sided limits and existence of a two-sided limit at a piecewise boundary
Consider the piecewise function
Using the definition of above, evaluate the left-hand limit and the right-hand limit . Based on these results, does exist? If it exists, state its value; if it does not, explain why not.
Hint
Remember that for near 2 but less than 2, you must use the formula , and for near 2 but greater than or equal to 2, you must use . Evaluate each piece as approaches 2 from its respective side.
Step-by-step solution
For the left-hand limit, since , we use . As , this expression approaches , so .
For the right-hand limit, since , we use . As , this expression approaches , so .
Since the left-hand limit (7) and the right-hand limit (4) are not equal, the two-sided limit does not exist. This is a case where the one-sided limits disagree, so the function does not settle to a single value as approaches 2.
Related problems
- Problem 18: One-sided limits and existence of a two-sided limit
- Problem 15: One-sided limits and existence of a two-sided limit at a piecewise breakpoint
- Problem 13: One-sided limits and existence of a two-sided limit at a piecewise boundary
- Problem 16: One-sided limits and existence of a two-sided limit at a piecewise breakpoint
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