JEE Mains · Maths · STD 11 - 8. sequence and series
In a geometric progression, if the ratio of the sum of first \(5\) terms to the sum of their reciprocals is \(49\), and the sum of the first and the third term is \(35\) . Then the first term of this geometric progression is
- A \(7\)
- B \(21\)
- C \(28\)
- D \(42\)
Answer & Solution
Correct Answer
(C) \(28\)
Step-by-step Solution
Detailed explanation
Accorrding to Question \( \Rightarrow \frac{{{S_5}}}{{S{'_5}}} = 49\) (here, \({S_5} = \) Sum of \(5\) terms and \({S_5} = \) Sum of their reciprocals)…
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