Non Differentiable Function

24 X 60 Washable Rug Washable Rugs 30 X 60 2X4 Rugs With Rubber Backing 24X60 Rug Runner Rug 2 X 6 Non Slip 20 X 48 Rugs 3X5 Washable Rugs With Non Skid Backing Non Slip Runner Mats Washable 3X5 Non Slip Rugs Rugs 24 X 48 Washable Rugs 3Ft X 10Ft Bathroom Runner Rugs 24 X 60 2X5 Runner Rug Non Slip Non Skid Runner Rugs 2X6 Runner Rug Non Slip 2X8 Runner Rug Non Slip 24X48 Rug 2 X 5 Washable Rug Washable Rug 60 Inches Long 24X60 Bathroom Rug Runner