The Negative Exponent Rule states that \( a^{-n} = \frac{1}{a^n} \).
Given the expression \( 3^{-1/2} \), we can apply this rule:
\[ 3^{-1/2} = \frac{1}{3^{1/2}} \]
The expression \( 3^{1/2} \) is equivalent to the square root of 3. Therefore, we can further simplify our expression:
\[ \frac{1}{3^{1/2}} = \frac{1}{\sqrt{3}} \]
Thus, an equivalent expression to \( 3^{-1/2} \) is:
\[ \frac{1}{\sqrt{3}} \]