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Sequences and Series question

2006 · Shift 0 · Q74

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JEE Main
Mathematics
Sequences and Series
2006 · Shift 0 · Q74

Sequences and Series question

2006 · Shift 0 · Q74

JEE MainMathematicsSequences and SeriesMCQ+4 / −1

If

{{a_1},{a_2},....{a_n}}

are in H.P., then the expression

{{a_1}\,{a_2} + \,{a_2}\,{a_3}\, + .... + {a_{n - 1}}\,{a_n}}

is equal to

A
$n({a_1}\, - {a_n})$
B
$(n - 1)({a_1}\, - {a_n})$
C
$n{a_1}{a_n}$
D
$(n - 1)\,\,{a_1}{a_n}$

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