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If a1,a2,...an are in H.P then the expre...

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

`n(a_(1)-a_(n))`

C

`(n-1)(a_(1)-a_(n))`

D

`na_(1)a_(n)`

Text Solution

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The correct Answer is:
A
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