JEE Mains · Maths · STD 11 - 8. sequence and series
The sum of the series \(1 + 2 \times 3 + 3 \times 5 + 4 \times 7 + .......\) upto \(11^{th}\) term is
- A \(915\)
- B \(946\)
- C \(945\)
- D \(916\)
Answer & Solution
Correct Answer
(B) \(946\)
Step-by-step Solution
Detailed explanation
\(S = 1 + 2 \times 3 + 3 \times 5 + 4 \times 7 + .... + \) upto \(11\) terms \({n^{th}}\)term of the series is \({T_n} = n\left( {2n - 1} \right)\) \( \Rightarrow S = \sum\limits_{n = 1}^{11} {{T_n}} = \sum\limits_{n = 1}^{11} {\left( {2{n^2} - n} \right)} \)…
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