Evaluate the sum to infinity: .

Answer and explanation

Correct answer: A.

  1. Step 1: Decompose the general summand into partial fractions: .
  2. 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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