An inflection point is a point on a curve at which the sign of the curvature (i.e., the concavity) changes. Inflection points may be stationary points, but are not local maxima or local minima. For example, for the curve plotted above, the point is an inflection point. The first derivative test can sometimes distinguish inflection points from extrema for differentiable functions . The second derivative test is also useful. A necessary condition for to be an inflection point is . A sufficient condition requires and to have opposite signs in the neighborhood of (Bronshtein and Semendyayev 2004, p. 231).
Rice vermicelli are thin rice-flour noodles common in Chinese, Thai, Vietnamese, and other Southeast Asian cuisines, where they are often used in stir-fries, soups, spring rolls, and salads. Don't confuse rice vermicelli with cellophane noodles, another thin Asian noodle that's made with mung bean starch.
More than 40,000 varieties of rice generally fall into one of three categories: short-, medium-, and long-grain. The most important differences are in cooking properties and taste. All rice is composed of two types of starch--dry and sticky. The dry starch, amylose, is higher in long-grain (indica) rice and, when cooked, produces drier rice with separate grains. The sticky starch, amylopectin, is higher in short-grain (japonica) rice and, when cooked, produces soft rice with clinging grains. Long-grain varieties are four to five times longer than wide.