`f(x) = 4^x` Find the derivative of the function

 To find the derivative, we will use the following formula:

`d/(dx)(a^x) = a^x*ln(a)* dx`

By comparison,  `a^x = 4^x ` then `a=4` , `x=x` , and` d/(dx)(x)=1`

Applying the formula, we get:

`f'(x) = 4^x*ln(4)* 1`

          ` =4^x ln(4)`

So, `f'(x)=4^x ln(4)` is the final answer