\[y = \sqrt[7]{x} - x\]
\[y( - x) = \sqrt[7]{( - x)} - ( - x) =\]
\[= - \sqrt[7]{x} + x = - \left( \sqrt[7]{x} - x \right) =\]
\[= - y(x).\]
\[Функция\ нечетная.\]