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If in a progression a1, a2, a3, e t cdo...

If in a progression `a_1, a_2, a_3, e t cdot,(a_r-a_(r+1))` bears a constant atio with `a_rxxa_(r+1)` , then the terms of the progression are in a. A.P b. G.P. c. H.P. d. none of these

A

A.P

B

G.P

C

H.P

D

none of these

Text Solution

Verified by Experts

The correct Answer is:
C

`(a_(r)-a_(r+1))/(a_(r)a_(r+1))=k` (constant)
`rArr1/(a_(r+1))-1/a_(r)=k`
`1/a_(1),1/a_(2),….,1/a_(n)` are in A.P.
`rArra_(1),a_(2),a_(3),…` are in H.P.
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