JEE Mains · Maths · STD 11 - 8. sequence and series
Let \(a_1, a_2, a_3, \ldots\) be a G.P. of increasing positive terms. If \(a_1 a_5=28\) and \(a_2+a_4=29\), then \(a_6\) is equal to:
- A \(628\)
- B \(812\)
- C \(526\)
- D \(784\)
Answer & Solution
Correct Answer
(D) \(784\)
Step-by-step Solution
Detailed explanation
\(\begin{aligned} & a_1 a_5=28 \Rightarrow a^2 r^4=28 \\ & a_2+a_4=29 \Rightarrow a r+a r^3=29 \end{aligned}\) ar and \(a r^3\) are roots of…
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