Answer
$3$
Work Step by Step
We want to break down the number $81$ to a small base raised to a power first:
$(3^4)^{1/4}$
Raising a power to a power means we can multiply the two exponents together, keeping the same base:
$3^{(4)(1/4)}$
Multiply to simplify the exponents:
$3^{4/4}$
Reduce the fraction in the exponent by dividing both numerator and denominator by $4$, the greatest common factor:
$3^{1}$
When we raise a number to the power of $1$, then the number can just be written as the base without an exponent:
$3$
