Stuck.....

Question

Is the sequence a geometric sequence? 10, 13, 16, 19, 22

Answer 1

Note that the sequence 10, 13, 16, 19, 22, ... follows a pattern of

 

x+(0)3, x+(1)3, x+(2)3, x+(3)3, ... which is not geometric.

 

The pattern is x_n = (x₀ + 3n); n=0,1,2,.. and x₀ = 10

Answer 2

In a geometric sequence a common ratio is present. 

Is 13/10 = 16/13? No, it is not a geometric sequence.

 

Yet, it could be an arithmetic that has a common difference.

Is 13 - 10 = 16 - 13? Yes, it is an arithmetic sequence.

Answer 3

Lucy, it is not. A geometric sequence is taking the first number and multiplying it by a fixed non-zero number, and so on.

 

What?? For example, 10, 20, 40, 80, 160... as we multiply by 2.

 

10 + 3 = 13 and 13 + 3 = 16, etc, but this is not a geometric sequence.