How do you identify if a sequence is geometric and how do you find the common ratio?

Question

anonymous · Answer

I think you can divide two adjacent terms to find the common ratio.  So try it with two different pairs will help in identifying if it's geo.

anonymous · Answer

do they all have to have the same quotient to be geometric?

isaidavila · Answer

For example:
1,2,4,8,16
That is a geométric sequence because the ratio is ×2.
The difference is that arithmetic sequence can only add or substract and in a geo you can multiply or divide

anonymous · Answer

oh, okay. Thank you

anonymous · Answer

yes, if they don't they don't share a common ratio