Answer :
Given:
The given geometric sequence is:
0.0625, 0.25, 1, ..., 4194304
To find:
The number of terms in the given geometric sequence.
Solution:
We have,
0.0625, 0.25, 1, ..., 4194304
Here, the first term is 0.0625 and the common ratio is:
[tex]r=\dfrac{0.25}{0.0625}[/tex]
[tex]r=4[/tex]
The nth term of a geometric sequence is:
[tex]a_n=ar^{n-1}[/tex]
Where, a is the first term and r is the common ratio.
Putting [tex]a_n=4194304, a=0.0625, r=4[/tex] in the above formula, we get
[tex]4194304=0.0625(4)^{n-1}[/tex]
[tex]\dfrac{4194304}{0.0625}=(4)^{n-1}[/tex]
[tex]67108864=(4)^{n-1}[/tex]
[tex]4^{13}=(4)^{n-1}[/tex]
On comparing both sides, we get
[tex]13=n-1[/tex]
[tex]13+1=n[/tex]
[tex]14=n[/tex]
Therefore, the number of terms in the given geometric sequence is 14.