Q8 of 110 Page 48

The sum of three terms of a geometric sequence is and their product is 1. Find the common ratio and the terms.


⇒ second term = a and third term = ar.


(where, r is common ratio)




……..(1)


Also, their product is 1.



⇒ a3 = 1


⇒ a = 1


Substituting a = 1 in equation (1)



⇒ 10 + 10r + 10r2 = 39r


⇒ 10r2-29r + 10 = 0


⇒ 10r2-25r-4r + 10 = 0


⇒ 5r(2r-5)-2(2r-5)


⇒ (5r-2) (2r-5) = 0



Now, G.P will be-






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