4) -1/2
1) Rewriting the expression:
![\frac{1}{\sqrt[]{x}}](https://img.qammunity.org/2023/formulas/mathematics/college/ptutcoxlje604ylym2se35vdvsjen53f09.png)
2) As a power we can write this way, considering that we can rewrite any radical as a power and that when we have a radical on the denominator we can rewrite it as a negative rational exponent. So we can write it out:
![\frac{1}{\sqrt[]{x}}=\frac{1}{x^{(1)/(2)}}=x^{-(1)/(2)}](https://img.qammunity.org/2023/formulas/mathematics/college/nl5deequljwurc8y3zm5y6httcp5bck2zc.png)
3) Hence, the answer is 4) -1/2