Sequence

Definition

A sequence is an ordered list of numbers or terms that follow a specific pattern or rule. Each number in a sequence is called a term, and sequences can be finite or infinite, depending on whether they have a defined end or continue indefinitely. Understanding sequences is crucial for grasping concepts related to series and summation notation, as these topics often involve adding the terms of a sequence together to find a sum.

5 Must Know Facts For Your Next Test

1. Sequences can be defined explicitly with a formula or recursively by specifying the initial terms and the rule for obtaining subsequent terms.
2. The notation for sequences typically uses 'a_n' to represent the nth term of the sequence, where 'n' is a positive integer.
3. Common examples of sequences include the Fibonacci sequence, which starts with 0 and 1, and each subsequent term is the sum of the two preceding ones.
4. Understanding how to derive the general term of a sequence is essential for using summation notation effectively when calculating series.
5. In summation notation, sequences can be represented with sigma (Σ) notation to indicate the sum of their terms over a specified range.

Review Questions

• How can you determine whether a given sequence is arithmetic or geometric?
  • To determine if a sequence is arithmetic, check if the difference between consecutive terms remains constant. If this difference is consistent, it indicates an arithmetic sequence. On the other hand, if each term after the first is obtained by multiplying the previous term by a fixed ratio, then it’s a geometric sequence. Recognizing these patterns helps classify sequences accurately.
• How does understanding sequences help in evaluating series using summation notation?
  • Understanding sequences provides the foundation for evaluating series through summation notation. Each series can be viewed as the sum of the terms in a sequence. By recognizing how to express sequences in mathematical terms, one can easily apply sigma notation to calculate sums over defined intervals. This connection enables efficient computation and analysis of series in various contexts.
• Analyze how different types of sequences, like arithmetic and geometric, impact real-world scenarios such as finance or biology.
  • Different types of sequences can model real-world scenarios effectively, influencing fields like finance and biology. For instance, arithmetic sequences can represent consistent savings plans where money is added at regular intervals, while geometric sequences can model population growth where numbers multiply over time. Understanding these sequences allows for better predictions and strategies in managing resources or studying trends, showcasing their practical applications in everyday life.

Related terms

Arithmetic Sequence: A sequence where each term after the first is obtained by adding a constant difference to the previous term.

Geometric Sequence: A sequence where each term after the first is obtained by multiplying the previous term by a fixed, non-zero number called the common ratio.

Recursive Formula: A formula that defines each term of a sequence in terms of one or more preceding terms.