Right-hand limit at x = 3
Consider the function defined for all . We want to investigate the behavior of as approaches .
Simplify for (where ), and use this to find
Hint
Factor the numerator as , then replace with since . Cancel the common factor before taking the limit.
Step-by-step solution
Factor the numerator: . For , we have , so . Thus for ,
Since for all near from the right, the right-hand limit is found by direct substitution into this simplified expression:
Left-hand limit at x = 3
Simplify for (where ), and use this to find
Hint
For , is negative, so . Substitute this into the simplified factored form of .
Step-by-step solution
As before, . For , we have , so . Thus for ,
Since for all near from the left, direct substitution gives
Existence of the two-sided limit
Based on your results from the previous two parts, does exist? If it exists, state its value; if not, explain why not.
Hint
Recall that a two-sided limit exists only when both one-sided limits exist and are equal to each other.
Step-by-step solution
From part (a), , and from part (b), . These two one-sided limits are not equal to each other.
Since the left-hand and right-hand limits disagree, the two-sided limit does not exist.
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