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If `a_1,a_2,.....a_n` are in H.P., then the expression `a_1a_2 + a_2a_3 + ... + a_(n-1)a_n` is equal to

A

`(n - 1)(a_1 - a_n)`

B

`na_1a_n`

C

`(n - 1) a_1a_n`

D

`n(a_1 - a_n)`

Text Solution

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The correct Answer is:
C
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