Answer:
[tex]\huge\boxed{\sqrt{(125^2)^{-\frac{1}{3}}}=\dfrac{1}{5}}[/tex]
Step-by-step explanation:
[tex]\sqrt{(125^2)^{-\frac{1}{3}}}\qquad\text{use}\ (a^n)^m=(a^m)^n\\\\=\sqrt{\left(125^{-\frac{1}{3}\right)^2}\qquad\text{use}\ \sqrt{a^2}=a\ \text{for}\ a\geq0\\\\=125^{-\frac{1}{3}}\qquad\text{use}\ a^{-n}=\dfrac{1}{a^n}\\\\=\dfrac{1}{125^\frac{1}{3}}\qquad\text{use}\ a^\frac{1}{n}=\sqrt[n]{a}\\\\=\dfrac{1}{\sqrt[3]{125}}=\dfrac{1}{5}\qquad\text{because}\ 5^3=125[/tex]