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More Lessons for Algebra II

More Lessons and Worksheets for Algebra

A series of free, online Intermediate Algebra Lessons or Algebra II lessons.

Videos, worksheets, and activities to help Algebra students.

**What is an Arithmetic Sequence?**

A list of numbers that follows a rule is called a sequence. Sequences whose rule is the addition of a constant are called arithmetic sequences, similar to geometric sequences that follow a rule of multiplication.

Homework problems on arithmetic sequences often ask us to find the nth term of a sequence using a formula. Arithmetic sequences are important to understanding arithmetic series.

**Arithmetic Sequences**

Determine the nth term of an arithmetic sequence.

Determine the common difference of an arithmetic sequence.

Determine the formula for an arithmetic sequence.

An arithmetic sequence is a sequence that has the pattern of adding a constant to determine consecutive terms. We say arithmetic sequences have a common difference.

Examples:

1. A sequence is a function. What is the domain and range of the following sequence?

2. Given the formula for the arithmetic sequence, determine the first 3 terms and the 8th term. Also state the common difference.

a_{n} = -4n + 3

3. Given the arithmetic sequence, determine the formula and the 12th term

-2,1.5,5,8.5,12,15.5, ...

**Introduction to Arithmetic Sequences**

Just a quick idea of what an arithmetic sequence is and a few examples

Examples:

Determine which of the following sequences are arithmetic. If they are arithmetic, give the value of 'd'. 1) 3,8,13,18,23,28,33, ...

2) -.7, -1.7, -2.7, -3.7, -4.7, ...

3) 1.6, 2.2, 2.8, 3.3, 3.9, 4.5, ...

4) 4/3, 5/3, 2, 7/3, 8/3, 3, ...

**Arithmetic Sequences: A Formula for the 'nth' Term**

This video derives the formula to find the 'n-th' term of a sequence by considering an example.

The formula is then used to do a few different problems.

Example:

Suppose we have the arithmetic sequence

3, 8, 13, 18, 23, 28, 33, ...

Find

a_{10}

a_{202}

**How to find the general term of an arithmetic sequence?**

a_{n} = a_{1} + (n-1)d

**What is an Arithmetic Series?**

We can use what we know of arithmetic sequences to understand arithmetic series. An arithmetic series is a series or summation that sums the terms of an arithmetic sequence.

There are methods and formulas we can use to find the value of an arithmetic series.

Understanding arithmetic series can help to understand geometric series, and both concepts will be used when learning more complex Calculus topics.

**Arithmetic Series**

Define a series.

Determine the partial sum of an arithmetic series.

Summing or adding the terms of an arithmetic sequence creates what is called a series.

S_{n} = n/2(a_{n} + a_{n})

Examples:

Determine the sum of the arithmetic series

1. 3 + 8 + 13 + ... + 73

2. a_{n} = -4n + 3; n = 20

**How to find the sum of an arithmetic series?**

How to find the sum of an arithmetic series when you're given only the first few terms and the last one?

Example:

Find the sum

-82, -80, -78, ... +64, +66

You can use the free Mathway calculator and problem solver below to practice Algebra or other math topics. Try the given examples, or type in your own problem and check your answer with the step-by-step explanations.

More Lessons for Algebra II

More Lessons and Worksheets for Algebra

A series of free, online Intermediate Algebra Lessons or Algebra II lessons.

Videos, worksheets, and activities to help Algebra students.

In this lesson, we will learn

- about arithmetic sequences
- how to find the formula for the nth term of an arithmetic sequence
- about arithmetic series
- how to find the sum of an arithmetic series

A list of numbers that follows a rule is called a sequence. Sequences whose rule is the addition of a constant are called arithmetic sequences, similar to geometric sequences that follow a rule of multiplication.

Homework problems on arithmetic sequences often ask us to find the nth term of a sequence using a formula. Arithmetic sequences are important to understanding arithmetic series.

Determine the nth term of an arithmetic sequence.

Determine the common difference of an arithmetic sequence.

Determine the formula for an arithmetic sequence.

An arithmetic sequence is a sequence that has the pattern of adding a constant to determine consecutive terms. We say arithmetic sequences have a common difference.

Examples:

1. A sequence is a function. What is the domain and range of the following sequence?

2. Given the formula for the arithmetic sequence, determine the first 3 terms and the 8th term. Also state the common difference.

a

3. Given the arithmetic sequence, determine the formula and the 12th term

-2,1.5,5,8.5,12,15.5, ...

Just a quick idea of what an arithmetic sequence is and a few examples

Examples:

Determine which of the following sequences are arithmetic. If they are arithmetic, give the value of 'd'. 1) 3,8,13,18,23,28,33, ...

2) -.7, -1.7, -2.7, -3.7, -4.7, ...

3) 1.6, 2.2, 2.8, 3.3, 3.9, 4.5, ...

4) 4/3, 5/3, 2, 7/3, 8/3, 3, ...

This video derives the formula to find the 'n-th' term of a sequence by considering an example.

The formula is then used to do a few different problems.

Example:

Suppose we have the arithmetic sequence

3, 8, 13, 18, 23, 28, 33, ...

Find

a

a

a

We can use what we know of arithmetic sequences to understand arithmetic series. An arithmetic series is a series or summation that sums the terms of an arithmetic sequence.

There are methods and formulas we can use to find the value of an arithmetic series.

Understanding arithmetic series can help to understand geometric series, and both concepts will be used when learning more complex Calculus topics.

Define a series.

Determine the partial sum of an arithmetic series.

Summing or adding the terms of an arithmetic sequence creates what is called a series.

S

Examples:

Determine the sum of the arithmetic series

1. 3 + 8 + 13 + ... + 73

2. a

How to find the sum of an arithmetic series when you're given only the first few terms and the last one?

Example:

Find the sum

-82, -80, -78, ... +64, +66

Rotate to landscape screen format on a mobile phone or small tablet to use the **Mathway** widget, a free math problem solver that **answers your questions with step-by-step explanations**.

You can use the free Mathway calculator and problem solver below to practice Algebra or other math topics. Try the given examples, or type in your own problem and check your answer with the step-by-step explanations.

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