SOLUTION: The three consecutive terms of exponential sequence are x-1,2x&5x+3,find(1)x(2) find common ratio(3) find the sum of the first five terms

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Question 1148435: The three consecutive terms of exponential sequence are x-1,2x&5x+3,find(1)x(2) find common ratio(3) find the sum of the first five terms
Answer by greenestamps(13203) About Me  (Show Source):
You can put this solution on YOUR website!


In an exponential sequence, the ratio of one term to the preceding term is constant. So

2x%2F%28x-1%29+=+%285x%2B3%29%2F%282x%29

5x%5E2-2x-3+=+4x%5E2
x%5E2-2x-3+=+0

%28x-3%29%28x%2B1%29+=+0

I'll let you finish working the problem from there.

Note solving the equation gives two values for x. Each of them produces a different common ratio and a different exponential sequence. But one of the sequences is not very interesting.

Note also that we would have no way of knowing the sum of the first five terms of the sequence, because your statement doesn't say WHICH terms of the sequence are represented by the given expressions.