Convex function than convex or strictly convex functions, since they are a smaller class. Like strictly convex functions, strongly convex functions have unique minima on compact sets. A uniformly convex function, with modulus formula_70, is a function that, for all "x", "y" in the domain and , satisfies where formula_70 is a function that is non-negative and vanishes only at 0. This is a generalization of the concept of strongly convex function; by taking formula_73 we recover the definition of strong convexity. Convex function In mathematics, a real-valued function defined on an "n"-dimensional interval is called convex (or convex downward or concave
Lens (optics) real object at the location of that virtual image. Likewise, it appears to a subsequent lens as if it were an object at that location, so that second lens could again focus that light into a real image, "S" then being measured from the virtual image location behind the first lens to the second lens. This is exactly what the eye does when looking through a magnifying glass. The magnifying glass creates a (magnified) virtual image behind the magnifying glass, but those rays are then re-imaged by the lens of the eye to create a "real image" on the retina.