AP EAMCET · Maths · Sequences and Series
For \(n \in N\), what is the value of \(1+4+7+\cdots+(3 n-2)\)
- A \(\frac{n(3 n+1)}{2}\)
- B \(\frac{(3 n-1)}{2}\)
- C \(\frac{n(3 n-1)}{2}\)
- D \(\frac{(3 n+1)}{2}\)
Answer & Solution
Correct Answer
(C) \(\frac{n(3 n-1)}{2}\)
Step-by-step Solution
Detailed explanation
\(S_n = \frac{n}{2}(a+l)\) \(S_n = \frac{n}{2}(1+(3n-2))\) \(S_n = \frac{n(3n-1)}{2}\)
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