Use the following function rule to find f(0). f(x) = 3(4)^x

1. Identify the function rule: The given function rule is $f(x) = 3(4)^x$. This is an exponential function.
2. Determine the value to substitute for x: The problem asks to find $f(0)$, which means we need to substitute $x=0$ into the function.
3. Substitute x=0 into the function: Replace every instance of $x$ in the function rule with $0$.
$f(0) = 3(4)^0$
4. Evaluate the exponent: Any non-zero number raised to the power of $0$ is $1$. So, $4^0 = 1$.
$f(0) = 3(1)$
5. Perform the multiplication: Multiply $3$ by $1$.
$f(0) = 3$
6. State the final answer: The value of the function when $x=0$ is $3$.