test

x {{\left( \sqrt[7]{x} \right)}^{\prime }}={{\left( {{x}^{\frac{1}{7}}} \right)}^{\prime }}=\frac{1}{7}{{x}^{\frac{1}{7}-1}}=\frac{1}{7}{{x}^{-\frac{6}{7}}}=\frac{1}{7}\frac{1}{{{x}^{\frac{6}{7}}}}=\frac{1}{7}\frac{1}{\sqrt[7]{{{x}^{6}}}}=\frac{1}{7\sqrt[7]{{{x}^{6}}}}