In mathematics, the trigonometric functions (also called the circular functions) are functions of an angle. They relate the angles of a triangle to the lengths of its sides. Trigonometric functions are important in the study of triangles and modeling periodic phenomena, among many other applications.
Yellow stool is generally a sign that food has passed through the digestive tract too quickly. Because bile salts from the liver give stool its brown color, yellow stool can indicate abnormalities with the gallbladder and liver. Healthgrades states that it can also be caused by an infection such as giardiasis.
Bilirubin concentration can vary the color of stool from light yellow to almost black. Changes in the chemical structure of the bilirubin can cause stool to turn green or yellow. Yellow stool also may occur if stool is dilute or there is a reduction in the amount of bilirubin that is produced by the liver. Bacteria and digestive enzymes in the intestine can act on the bilirubin and change its color. Most stool-to-stool changes in color have little meaning.