Algebra Examples

- 3

$- 3$ ,

3

$3$ ,

- 3

$- 3$ ,

3

$3$

Step 1

This is a geometric sequence since there is a common ratio between each term. In this case, multiplying the previous term in the sequence by

- 1

$- 1$ gives the next term. In other words,

a_{n} = a_{1} r^{n - 1}

$a_{n} = a_{1} r^{n - 1}$ .

Geometric Sequence:

r = - 1

$r = - 1$

Step 2

This is the form of a geometric sequence.

a_{n} = a_{1} r^{n - 1}

$a_{n} = a_{1} r^{n - 1}$

Step 3

Substitute in the values of

a_{1} = - 3

$a_{1} = - 3$ and

r = - 1

$r = - 1$ .

a_{n} = - 3 {(- 1)}^{n - 1}

$a_{n} = - 3 {(- 1)}^{n - 1}$