Classify the discontinuity of r(x) at x = 2
Consider the function which is undefined at .
The function is not defined at . Determine whether exists, and use this to classify the discontinuity at as removable, jump, or infinite. If the discontinuity is removable, state the value that would need to be assigned at in order to make it continuous there.
Hint
Factor the numerator as a difference of cubes: , then simplify the fraction before taking the limit.
Step-by-step solution
Factor the numerator using the difference of cubes formula: . For , this lets us cancel the common factor of , giving whenever .
Since agrees with the polynomial for all near but not equal to , the limit as exists and equals . Because is undefined but the limit exists (and is finite), this is a removable discontinuity — the graph has a hole at that could be patched by defining .
Feature of the graph at the removable discontinuity
Hint
Step-by-step solution
The graph shows a hole. Since the discontinuity at x equals two is removable, the limit exists and equals twelve, but the function value there is undefined. This creates a single missing point on an otherwise continuous curve, which is visually represented as a hole rather than a jump or a break from an asymptote.
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