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Sequences and Series question

2024 · 29 Jan · Shift 2 · Q46

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JEE Main
Mathematics
Sequences and Series
2024 · 29 Jan · Shift 2 · Q46

Sequences and Series question

2024 · 29 Jan · Shift 2 · Q46

JEE MainMathematicsSequences and SeriesMCQ+4 / −1

If each term of a geometric progression

a_1, a_2, a_3, \ldots

with

a_1=\frac{1}{8}

and

a_2 eq a_1

, is the arithmetic mean of the next two terms and

S_n=a_1+a_2+\ldots . .+a_n

, then

S_{20}-S_{18}

is equal to

A
$-2^{15}$
B
$2^{15}$
C
$-2^{18}$
D
$2^{18}$

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