Answer:
[tex]a_n = (\frac{1}{4})2^{n-1}[/tex]
Step-by-step explanation:
Geometric sequence:
In a geometric sequence, the quotient between consecutive terms is the same, and this quotient is given by q.
The explicit rule of a geometric sequence is given by:
[tex]a_n = a_1q^{n-1}[/tex]
In which [tex]a_1[/tex] is the first term.
1/4, 1/2, 1, 2, 4
This means that [tex]a_1 = \frac{1}{4}[/tex], and:
[tex]q = \frac{4}{2} = \frac{2}{1} = \frac{1}{\frac{1}{2}} = \frac{\frac{1}{2}}{\frac{1}{4}} = 2[/tex]
So the explicit rule is:
[tex]a_n = (\frac{1}{4})2^{n-1}[/tex]
