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Q. if x1,x2......xn are in H.P., then su...

Q. if `x_1,x_2......x_n` are in `H.P`., then `sum_(r=1)^n 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) `(n+2)x_1 x_n`

A

`(n-1)x_1 x_n`

B

`n x_1 x_n`

C

`(n+1) x_1 x_n`

D

`(n+2)x_1 x_n`

Text Solution

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The correct Answer is:
A
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