Let f be: R?R given by f(x,y) = (y - x) (y 2x)Show that f has no local minimum at (0,0), but that every

Let f be: R²?R given by f(x,y) = (y - x²) (y – 2x²)Show that f has no local minimum at (0,0), but that every restriction flg for every line G?R² through the origin, has a local minimum at (0,0).