Progression (Sequence and Series)Medium
Question
Let Tr be the rth term of a sequence for r = 1,2,3,..... such that 
and tr > 0 ∀ r ∈ N. If sum of first n terms of this sequence is 
and maximum value of T5 is 
where p & q arecoprime numbers then value of (p + q) is -
and tr > 0 ∀ r ∈ N. If sum of first n terms of this sequence is and maximum value of T5 is where p & q arecoprime numbers then value of (p + q) is -Options
A.3381
B.3268
C.3496
D.3167
Solution
Sequence is G.P
Sn =
= (1 - rn)
⇒ a = 1 - r
Now T5 = ar4 = (1 - r)r4
maximum exist when r =
(T5)max =
Sn =
= (1 - rn)⇒ a = 1 - r
Now T5 = ar4 = (1 - r)r4
maximum exist when r =
(T5)max =
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