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If a1,a2,a3,a4 are in HP , then 1/(a...

If `a_1,a_2,a_3,a_4` are in `HP` , then `1/(a_1a_4)sum_(r=1)^3a_r a_(r+1)` is root of :

A

`x^2 + 2x + 15 =0`

B

`x^2 + 2x -15 =0`

C

`x^2 - 2x +15 =0`

D

`x^2 - 2x -15=0`

Text Solution

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The correct Answer is:
B
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