Question

S is a geometric sequence.

a) (√x + 1), 1 and (√x-1) are the first three terms of S.
Find the value of x.
You must show all your working.

Answer 1

It will have a common ratio if it’s a gp
So 1/(sqrt x+1= (sqrt x -1)
(Sqrt x +1)(sqrt -1) = 1
X-1. = 1
X = 2