To represent the geometric sequence 6, 18, 54, ..., we need to identify the first term and the common ratio.
- The first term \( a = 6 \).
- The common ratio \( r = \frac{18}{6} = 3 \).
The general formula for the \( n \)-th term of a geometric sequence can be written as:
\[ f(n) = a \cdot r^{(n-1)} \]
Substituting \( a = 6 \) and \( r = 3 \):
\[ f(n) = 6 \cdot 3^{(n-1)} \]
Thus, the correct representation of the sequence is:
f(x) = 6(3)^(x-1)
So the correct response would be:
f(x) = 6(3)^(x-1)