To simplify the expression $3^{-4/3}$, follow these steps:

1. Understand the negative exponent: A negative exponent indicates the reciprocal of the base raised to the corresponding positive exponent. So, $3^{-4/3}$ can be rewritten as: $\frac{1}{3^{4/3}}$

2. Simplify the fractional exponent: The exponent $4/3$ means ( 3