Respuesta :

5th term = a1r^4   where a1 = first term and r = common ratio

so 1/4 = a1 * (1/2)^4

a1 = 1/4 / (1/2)^4  =  4

so the sequence  is  4 , 4*1/2, 4*(1/2)^2...

= 4, 2, 1, 1/2, 1/4 .....

Answer:

4, 2, 1, [tex]\frac{1}{2}[/tex].......

Step-by-step explanation:

Since explicit formula of a geometric sequence is represented by An = [tex]A_{1}(r)^{n-1}[/tex]

It is given in the question that fifth term of the sequence is [tex](\frac{1}{4})[/tex] and common ratio of the sequence is [tex]\frac{1}{2}[/tex].

Now from the explicit formula

[tex]A_{5}=\frac{1}{4} =A_{1}(\frac{1}{2})^{5-1}[/tex]

[tex]\frac{1}{4}=A_{1}( \frac{1}{2})^{4}[/tex]

[tex]A_{1} \frac{2^{4} }{4}[/tex]

[tex]\frac{16}{4}[/tex] = 4

Therefore, sequence will be 4, 4 × [tex](\frac{1}{2})[/tex], 4 × [tex]\frac{1}{2}^{2}[/tex], 4 × [tex](\frac{1}{2})[/tex]³.........

= 4, 2, 1, [tex]\frac{1}{2}[/tex].......