Answer
$3.1\sqrt[3] x^{4}-\frac{11}{7\sqrt[7] x}$
Work Step by Step
$\frac{3.1}{x^{-\frac{4}{3}}}-\frac{11}{7}x^{-\frac{1}{7}}=\frac{3.1}{\frac{1}{x^{\frac{4}{3}}}}-\frac{11}{7}\times\frac{1}{x^{\frac{1}{7}}}=3.1x^{\frac{4}{3}}-\frac{11}{7x^{\frac{1}{7}}}=3.1\sqrt[3] x^{4}-\frac{11}{7\sqrt[7] x}$
