Question

What is an explicit formula for the geometric sequence 64,16,4,1,... where the first term

Answer 1

Answer:

A

Step-by-step explanation:

The explicit formula for a geometric sequence is

f(n) = f(1) $(r)^{n-1}$

where f(1) is the first term and r the common ratio

Here f(1) = 64 and r = $\frac{f(2)}{f(1)}$ = $\frac{16}{64}$ = $\frac{1}{4}$ , then

f(n) = 64 $(\frac{1}{4}) ^{n-1}$ → A