Their stems are typically flattened, almost leaf-like in appearance, with fewer or even no spines, such as the well-known Christmas cactus or Thanksgiving cactus (in the genus Schlumbergera). Cacti have a variety of uses: many species are used as ornamental plants, others are grown for fodder or forage, and others for food (particularly their fruit).
1 Car of Tomorrow, a car design used in NASCAR racing. 2  Cost of transport, an energy calculation. 3  Cotangent, a trigonometric function, written as cot.  Cotyledon, a significant part of the embryo within the seed of a plant.
Example 1: Evaluate . Because cot x = cos x/sin x, you find The numerator approaches 1 and the denominator approaches 0 through positive values because we are approaching 0 in the first quadrant; hence, the function increases without bound and and the function has a vertical asymptote at x = 0. Example 4: Evaluate .