39.9k views
4 votes
Determine if the sequence is arithmetic or geometric. Please explain your answer, listing any three consecutive terms from the sequence: 5, -(10/3), (20/9), -(40/27), (80/81), ...

User Uncle Dan
by
7.8k points

1 Answer

5 votes

Final answer:

The sequence is a geometric sequence with a common ratio of -(2/3), identified by dividing each term by the previous term and finding a constant ratio.

Step-by-step explanation:

To determine if the sequence is arithmetic or geometric, we should look at the pattern of the terms in the sequence. An arithmetic sequence has a constant difference between consecutive terms, while a geometric sequence has a constant ratio between consecutive terms. Let's choose three consecutive terms to analyze: -(10/3), (20/9), and -(40/27).

  • For an arithmetic sequence, we would expect each term to be obtained by adding a fixed number to the previous term.
  • For a geometric sequence, each term is obtained by multiplying the previous term by a fixed number.

Let's check for a constant ratio by dividing each term by the previous term:

  • (20/9) ÷ (-(10/3)) = -(20/9) * (-(3/10)) = (60/90) = (2/3)
  • -(40/27) ÷ (20/9) = -(40/27) * (9/20) = -(360/540) = -(2/3)

Notice that when we divide each term by the previous term, we get the same ratio of -(2/3). This indicates that the sequence is indeed a geometric sequence with a common ratio of -(2/3).

User Ufollettu
by
8.3k points