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Let a,b,c be in A.P. and |a|lt1,|b|lt1|c...

Let `a,b,c` be in A.P. and `|a|lt1,|b|lt1|c|lt1.` if `x=1+a+a^(2)+ . . . . oo`,
`y=1+b+b^(2)+ . . . .oo`,
`z=1+c+c^(2)+ . . . oo`, then `x,y,z` are in

A

AP

B

GP

C

HP

D

None of these

Text Solution

Verified by Experts

The correct Answer is:
C
Clearly, `x=(1)/(1-a),y=(1)/(1-b)" and "z=(1)/(1-c)`
Since, a,b,c are in AP.
`implies 1-a,1-b,1-c` ,are also in AP.
`implies (1)/(1-a),(1)/(1-b),(1)/(1-c)` are in HP.
`:. X,y,z` are in HP.
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