You are having a discussion about sequences with your classmate. She insists that the sequence 2, 3, 5, 8, 12 must be either arithmetic or geometric. Is she correct or incorrect? Explain

your answer.

She is incorrect. A sequence can be neither arithmetic nor geometric. It can be a combination of the two, or it can be neither.

The bot is actually correct to say it is neither arithmetic nor geometric.

As a matter of fact the sequence can be considered quadratic, since

term(n) = (n^2 - n + 4)/2, where n ∈ N

Your classmate is incorrect. The sequence 2, 3, 5, 8, 12 is neither arithmetic nor geometric.

An arithmetic sequence is a sequence in which the difference between consecutive terms is constant. In this case, the difference between each term is not the same. For example, the difference between the first two terms is 3 - 2 = 1, but the difference between the second and third terms is 5 - 3 = 2, which is not the same. Therefore, this sequence is not arithmetic.

A geometric sequence is a sequence in which each term is obtained by multiplying the previous term by a constant factor. In this case, the ratios between consecutive terms are not the same. For example, the ratio between the second and first terms is 3/2, but the ratio between the third and second terms is 5/3, which is not the same. Therefore, this sequence is not geometric either.

Hence, the sequence 2, 3, 5, 8, 12 is neither arithmetic nor geometric.

To determine whether the sequence 2, 3, 5, 8, 12 is arithmetic or geometric, we need to check if there is a common difference or a common ratio between consecutive terms of the sequence.

First, let's check if it is an arithmetic sequence. In an arithmetic sequence, each term is obtained by adding a constant difference to the previous term. To see if this is the case, we can calculate the differences between consecutive terms:

3 - 2 = 1
5 - 3 = 2
8 - 5 = 3
12 - 8 = 4

Looking at the differences, we notice that they are not constant. The differences are increasing: 1, 2, 3, 4. Therefore, the sequence 2, 3, 5, 8, 12 is not an arithmetic sequence.

Now let's check if it is a geometric sequence. In a geometric sequence, each term is obtained by multiplying the previous term by a constant ratio. To determine if this holds true for our sequence, we can calculate the ratios between consecutive terms:

3 / 2 = 1.5
5 / 3 ≈ 1.67
8 / 5 = 1.6
12 / 8 = 1.5

Again, the ratios are not constant. They are approximately 1.5, 1.67, 1.6. Therefore, the sequence 2, 3, 5, 8, 12 is not a geometric sequence either.

In conclusion, your classmate is incorrect. The sequence 2, 3, 5, 8, 12 is neither arithmetic nor geometric.