JEE Mains · Maths · STD 11 - 8. sequence and series
If the sum of the first \(n\) terms of the series \(\sqrt 3 + \sqrt {75} + \sqrt {243} + \sqrt {507} + ......\) is \(435\sqrt 3 \) , then \(n\) equals
- A \(18\)
- B \(15\)
- C \(13\)
- D \(29\)
Answer & Solution
Correct Answer
(B) \(15\)
Step-by-step Solution
Detailed explanation
\(\sqrt 3 \left[ {1 + \sqrt {25} + \sqrt {81} + \sqrt {69} + .....} \right] = 435\sqrt 3 \) \( \Rightarrow \sqrt 3 = \left[ {1 + 5 + 9 + 13 + ..... + {T_n}} \right] = 435\sqrt 3 \)…
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