JEE MATHEMATICS MCQ: SEQUENCE OF SERIES

1 Easy

1 of 1

Application +4 | -1

a_1, a_2, \ldots, a_n

are in

\mathrm{HP}

, then the expression

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

is equal to

View answer and explanation

Correct option: D

(n-1) a_1 a_n

Option D (

(n-1) a_1 a_n

) is correct because the sum of the product of consecutive terms in a harmonic progression can be simplified to this expression.

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