SOLUTION: The first term of G.P is x and the third term is y. Find an expression for the common ratio in terms of x and y

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Question 1030380: The first term of G.P is x and the third term is y. Find an expression for the common ratio in terms of x and y
Answer by robertb(5830) About Me  (Show Source):
You can put this solution on YOUR website!
The first three terms of the GP are
x, s, y,...
The common ratio r is equal to both s/x and y/s, and s%2Fx+=+y%2Fs, or s%5E2+=+xy.
==> s+=+sqrt%28xy%29 or s+=+-sqrt%28xy%29
==> Common ratio r is equal to either sqrt%28xy%29%2Fx+=+sqrt%28y%2Fx%29, or -sqrt%28y%2Fx%29