Answer the questions below. Use the Format Editor x−−√ to type math or use the Image icon to upload a photo of your work.

Is the sequence arithmetic or geometric?
Does it have a common difference or common ratio?
What is the common difference or common ratio?
What are the next three terms?
−7, −4, −1, 2, 5, . . .

1 answer

To determine whether the given sequence \(-7, -4, -1, 2, 5, \ldots\) is arithmetic or geometric, we need to analyze the differences between the consecutive terms.

  1. Check if the sequence is arithmetic:
    • The difference between the first term and the second term: \[ -4 - (-7) = -4 + 7 = 3 \]
    • The difference between the second term and the third term: \[ -1 - (-4) = -1 + 4 = 3 \]
    • The difference between the third term and the fourth term: \[ 2 - (-1) = 2 + 1 = 3 \]
    • The difference between the fourth term and the fifth term: \[ 5 - 2 = 3 \]

Since the difference between all consecutive terms is the same (3), the sequence is an arithmetic sequence.

  1. Common Difference: The common difference is \(3\).

  2. Next Three Terms: To find the next three terms, we can continue adding the common difference of \(3\):

    • Next term after \(5\): \[ 5 + 3 = 8 \]
    • Next term after \(8\): \[ 8 + 3 = 11 \]
    • Next term after \(11\): \[ 11 + 3 = 14 \]

Thus, the next three terms in the sequence are \(8, 11, 14\).

Summary:

  • The sequence is arithmetic.
  • It has a common difference of \(3\).
  • The common difference is \(3\).
  • The next three terms are \(8, 11, 14\).