Behavior near a vertical asymptote
Consider the function
Identifying a removable discontinuity
Factor the numerator and denominator of to determine the behavior as . Note that is a zero of the denominator. Check whether is also a zero of the numerator. After factoring completely, determine . Your answer should be , , a finite value, or a statement that the two-sided limit does not exist because the one-sided limits disagree in sign.
Hint
Factor and completely. Check whether the factor appears in both the numerator and denominator. If it cancels, you have a removable discontinuity. If it doesn't cancel from the denominator, you have a vertical asymptote.
Step-by-step solution
Factor both polynomials: and . Canceling the common factor (valid since ) gives for . This simplified form reveals that near , the numerator approaches while the denominator approaches , both nonzero.
Since as , and this is a finite nonzero value, the original limit is actually finite, not infinite. Evaluating directly: . Because the factor causing the zero denominator canceled, is a removable discontinuity (a hole), not a vertical asymptote, so the limit exists and equals .
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