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 typically due to an excess of fatty foods and grease in the diet. Mayo Clinic states that it can also be caused by a malabsorption disorder such as celiac disease.
As the bile travels through the bowel, it turns yellow, then brown. If stool is moving fast through the bowel, it doesn't have time to turn brown, so it may come out yellow or even green. Stool travels faster when the bowel is irritated, such as when there is a virus.