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If x1,x2 , …. xn are in H.P. then sum(r...

If `x_1,x_2` , …. `x_n` are in H.P. then `sum_(r=1)^(n-1) x_r x_(r+1)` is equal to :

A

`(n-1)x_(1).x_(n)`

B

`n.x_(1).x_(n)`

C

`(n+1)x_(1).x_(n)`

D

none of these

Text Solution

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The correct Answer is:
A
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