Clinician definition, a physician or other qualified person who is involved in the treatment and observation of living patients, as distinguished from one engaged in research. See more. Dictionary.com
In geometry, the foci (/ËfoÊsaÉª/ ; singular focus) are a pair of special points with reference to which any of a variety of curves is constructed. For example, foci can be used in defining conic sections, the four types of which are the circle, ellipse, parabola, and hyperbola. In addition, foci are used to define the Cassini oval and the Cartesian oval.
7.1 Alternative Characterization. Assume given a point F in the plane, a line d not going through F, and a positive real number e. The set of points P such that the distance PF is e times the distance from P to d (measured along a perpendicular) is a conic. We call F the focus, d the directrix and e the eccentricity of the conic. If e e =1 a parabola, and if e 1).