What is the value of ?
Answer and explanation
Correct answer: E.
- Step 1: Use partial fractions: .
- Step 2: The sum telescopes: .
- Step 3: That is .
Answer
.
Why not the others: is the limit of the infinite sum, not of the first terms; is the sum of the first terms; is the sum of the first terms; is the sum of the first terms.
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