Respuesta :

Given:

The sequence is:

12, 6, 3, ...

To find:

The formula for the nth term of the given sequence.

Solution:

We have,

12, 6, 3, ...

Here, first term is 12.

Clearly, [tex]\dfrac{6}{12}=\dfrac{3}{6}[/tex]. Since the given sequence has a common ratio [tex]r=dfrac{1}{2}[/tex], therefore it is a geometric sequence.

The formula for the nth term of the given sequence is:

[tex]a_n=ar^{n-1}[/tex]

Where, a is the first term and r is the common ratio.

[tex]a_n=12\left(\dfrac{1}{2}\right)^{n-1}[/tex]

Therefore, the formula for the nth term of the given sequence is [tex]a_n=12\left(\dfrac{1}{2}\right)^{n-1}[/tex].