Right-hand limit of f(x) as x approaches -1
Consider the function . We want to investigate the behavior of as approaches .
Evaluate for values of slightly greater than (such as ) to build a table of values. Based on this trend, what is ?
Hint
For , the quantity is positive, so . Simplify under this assumption before plugging in values close to .
Step-by-step solution
When , we have , so . Substituting into gives for all such .
Since equals the constant value for every slightly greater than , the values in the table stay fixed at and do not change as . Therefore .
Left-hand limit of f(x) as x approaches -1
Now evaluate for values of slightly less than (such as ) to build a table of values. Based on this trend, what is ?
Hint
For , the quantity is negative, so . Simplify under this assumption before plugging in values close to .
Step-by-step solution
When , we have , so . Substituting into gives for all such .
Since equals the constant value for every slightly less than , the values in the table stay fixed at as . Therefore .
Existence of the two-sided limit
Using your results for the one-sided limits from parts (a) and (b), does exist? Justify your conclusion.
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), .
Since the left-hand limit and right-hand limit are not equal (), the two-sided limit does not exist.
Sign of the constant value approached from the right
Hint
Step-by-step solution
The right-hand limit found in part (a) was one, which is positive. This occurred because for x slightly greater than negative one, the function simplified to the constant value one. Since this value stays fixed and never changes sign as x approaches negative one from the right, the answer is positive.
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