Let `A_r ,r=1,2,3, `
, be the points on the number line such that `O A_1,O A_2,O A_3dot`
are in `G P ,`
where `O`
is the origin, and the common ratio of the `G P`
be a positive proper fraction. Let `M ,`
be the middle point of the line segment `A_r A_(r+1.)`
Then the value of `sum_(r=1)^ooO M_r`
is equal to
`(O A_1(O S A_1-O A_2))/(2(O A_1+O A_2))`
(b) `(O A_1(O A_1-O A_2))/(2(O A_1+O A_2)`
`(O A_1)/(2(O A_1-O A_2))`
(d) `oo`
A. `(OA_1(OA_1-OA_2))/(2(OA_1+OA_2))`
B. `(OA_1(OA_1+OA_2))/(2(OA_1-OA_2))`
C. `(OA_1)/(2(OA_1-OA_2))`
D. `prop`