Evaluate the sum to infinity: .
Answer and explanation
Correct answer: A.
- Step 1: Decompose the general summand into partial fractions: .
- Step 2: Write out the telescoping partial sum: . Taking the limit as yields .
Answer
.
Why not the others: The fraction represents only the second boundary term; the value results from erroneously summing the reciprocal integers; claiming divergence confuses the telescoping series with the harmonic series.
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