Checking the three-part continuity test at x = 2
Consider the function
Determine whether is continuous at . To justify your answer, check each of the three conditions required for continuity at a point: (1) is defined, (2) does exist, and (3) does that limit equal ? Based on your findings, state whether is continuous at , and if not, classify the discontinuity as removable, jump, or infinite.
Hint
Factor as to simplify the fraction for , then use this simplified form to evaluate the limit as . Compare that limit value to the given value .
Step-by-step solution
First check condition 1: is given directly in the definition as , so this value is defined. Next, for , simplify , since allows cancellation. This simplification lets us compute the limit using a polynomial expression instead of the original rational expression.
Now check condition 2: , so the limit exists and equals . Finally check condition 3: compare the limit value to — they are not equal, so condition 3 fails. Therefore is not continuous at . Since the limit exists but does not equal , this is a removable discontinuity.
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