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Sequences and Series question

2025 · 2 Apr · Shift 1 · Q45

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JEE Main
Mathematics
Sequences and Series
2025 · 2 Apr · Shift 1 · Q45

Sequences and Series question

2025 · 2 Apr · Shift 1 · Q45

JEE MainMathematicsSequences and SeriesMCQ+4 / −1

Let

a_1, a_2, a_3, \ldots

be in an A.P. such that

\sum_{k=1}^{12} a_{2 k-1}=-\frac{72}{5} a_1, a_1 eq 0

. If

\sum_{k=1}^n a_k=0

, then

n

is :

A
18
B
17
C
11
D
10

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