the sum of first three terms of a G.P. is 12/13 and their product is -1, find G.P.
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(Hey i think you mistacly write 12/13 it is 13/12)
Let the three terms be a/r,ar and a
When we take the product of three terms the common ratio gets cancelled
a/r*a*ar=a³=(-1)^3=-1
a=-1
sum of three terms is 13/12
a+a/r+ar=13/12
-1-1/r-r=13/12
-1/r-r=13/12+1
-1/r-r=25/12
(r-9)(r-16)=0
r=9 or r=16
the terms for r=9
-1,-9,-1/9
for r=16
-1,-16,-1/16
Let the three terms be a/r,ar and a
When we take the product of three terms the common ratio gets cancelled
a/r*a*ar=a³=(-1)^3=-1
a=-1
sum of three terms is 13/12
a+a/r+ar=13/12
-1-1/r-r=13/12
-1/r-r=13/12+1
-1/r-r=25/12
(r-9)(r-16)=0
r=9 or r=16
the terms for r=9
-1,-9,-1/9
for r=16
-1,-16,-1/16
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