# What is an expression for a sequence?

## What is an expression for a sequence?

A sequence is an ordered list of numbers . In the sequence 1, 3, 5, 7, 9, …, 1 is the first term, 3 is the second term, 5 is the third term, and so on. The notation a 1, a 2, a 3,… a n is used to denote the different terms in a sequence. The expression a n is referred to as the general or nth term of the sequence.

## What is the TN formula?

The formula for the nth term is given by: Tn = a + (n − 1)d = dn + (a − d) (2) where a and d are fixed and n is the variable (integer ≥ 1). This corresponds to y = mx + b where m and b are fixed and x variable.

What are the examples of arithmetic sequence?

Sequences with such patterns are called arithmetic sequences. In an arithmetic sequence, the difference between consecutive terms is always the same. For example, the sequence 3, 5, 7, 9 is arithmetic because the difference between consecutive terms is always two.

### What is the formula for nth term of an arithmetic sequence?

The nth term of an arithmetic sequence is given by. an = a + (n – 1)d. The number d is called the common difference because any two consecutive terms of an. arithmetic sequence differ by d, and it is found by subtracting any pair of terms an and. an+1.

### What is sequence with example?

A sequence is a list of numbers in a certain order. Each number in a sequence is called a term . Each term in a sequence has a position (first, second, third and so on). For example, consider the sequence {5,15,25,35,…} In the sequence, each number is called a term.

What is the nth term formula?

## How to find the common difference in an arithmetic sequence?

So let’s find the common difference by taking each term and subtracting it by the term that comes before it. The common difference here is positive four (+ 4) which makes this an increasing arithmetic sequence. We can obtain the next three terms by adding the last term by this common difference.

How to write a formula for an arithmetic sequence?

How To: Given an arithmetic sequence, write its recursive formula. Subtract any term from the subsequent term to find the common difference. State the initial term and substitute the common difference into the recursive formula for arithmetic sequences. Write a recursive formula for the arithmetic sequence.

### How to find the total number of terms in an arithmetic sequence?

How To: Given the first three terms and the last term of a finite arithmetic sequence, find the total number of terms. 1 Find the common difference d d. 2 Substitute the common difference and the first term into an = a1 +d(n−1) a n = a 1 + d ( n − 1). 3 Substitute the last term for an a n and solve for n n.

### When does an arithmetic sequence become a decreasing sequence?

Don’t assume that if the terms in the sequence are all negative numbers, it is a decreasing sequence. Remember, it is decreasing whenever the common difference is negative. So let’s find the common difference by taking each term and subtracting it by the term that comes before it.