Answer:
[tex]x^{\frac{21}{5}}[/tex]
Step-by-step explanation:
[tex]5^{th} \ root \ of \ x^7 = (x^ 7)^{\frac{1}{5}}[/tex]
[tex]Using \ the \ rule : \sqrt[n]{x} =x^{\frac{1}{n}} \\\\(x^a)^b = x^{ab}[/tex]
[tex](x^7)^{\frac{1}{5}} = x^{\frac{7}{5}}[/tex]
[tex]( x^{\frac{7}{5}})^3 = x^{\frac{21}{5}}[/tex]
