Math and Calculus teachers should get this pun right away. It means the derivative of milk equals cheese. The letters represent finding the derivative of a function. Place this humorous graphic on a t-shirt, ball cap, sweater, sweatshirt, pillow, mug, poster, or some other item or gift. Makes a great gift for yourself or that Math or Calculus teacher you know and love. This cut file pack includes svg, png, jpg, eps, pdf, and dxf file formats.***These files are for personal use only.The extr