Write the equation in exponential form. \( \log _{3} 81=4 \) \( [?]=\square \)

To convert the logarithmic equation \( \log_{3} 81 = 4 \) into exponential form, we can use the definition of a logarithm. This tells us that the base (which is 3) raised to the power of the result (which is 4) gives us the argument (which is 81). So, we write it as: \[ 3^{4} = 81 \] This means that if you take 3 and multiply it by itself four times (which is \( 3 \times 3 \times 3 \times 3 \)), you indeed get 81. So, we have \( [3^{4} = 81] = \square \).