To find \( f(5) \) using the formula \( f(x) = 4000(1.06)^x \), we substitute \( x = 5 \):
\[ f(5) = 4000(1.06)^5 \]
Calculating \( (1.06)^5 \):
\[ (1.06)^5 \approx 1.338225 \]
Now, multiply this result by 4000:
\[ f(5) = 4000 \times 1.338225 \approx 5352.90 \]
So, rounding to the nearest cent:
\[ f(5) \approx 5352.90 \]
Thus, the amount of money in the bank at the end of 5 years will be:
\[ \boxed{5352.90} \]