
How to remember which function is concave and which one is convex?
If you know the standard English meaning of the words convex and concave, you can remember that for a convex function it is the epigraph that is convex, and for a concave function it is the epigraph that is …
Is $g (x)=\log x$ convex function? - Mathematics Stack Exchange
Mar 27, 2015 · It is (strictly) concave. However, some books or lecture notes use "convex" for both convex and concave, adding an adjective "upward" or "downward" -- which can be confusing.
convex analysis - Convexity, Hessian matrix, and positive semidefinite ...
Then, if the determinant of the Hessian matrix is greater than $0$, then the function is strictly convex. If the determinant of the Hessian is equal to $0$, then the Hessian is positive semi-definite and the …
optimization - Convexity and concavity with Hessian matrices ...
Sep 29, 2018 · I want to analyze two Hessian matrices regarding definiteness to formulate conclusions whether the functions are convex or concave. If you could check my thoughts, I’d be grateful.
What's the difference between quasi-concavity and concavity?
Nov 1, 2017 · What's the intuitive difference between quasi-concavity and concavity? Can you give an example of a quasi-concave function that is not concave?
soft question - Why does "convex function" mean "concave *up ...
Concave (inward-curved) lenses are the opposite of convex lenses, so there is a pre-existing word for "not convex" or "convex in the opposite direction". Convex has an absolutely entrenched …
The composition of two convex functions is convex
@Lost1, there are actually four such rules, for each combination of convex/concave inner and outer functions: convex-nondecreasing & convex -> convex, convex-nonincreasing & concave -> convex, …
How to determine whether a function is concave, convex, quasi …
Sep 5, 2015 · quasi convex quasi concave, and semi-strict quasi concave and semi-strict quasi convex, and strictly quasi concave and strictly quasi concave. In addition it will be strictly pseudo convex. as …
convex analysis - convexity of inverse function - Mathematics Stack ...
3 Because you didn't specify the domain and range, assume f is a real function. Also, so the inverse is defined, assume f is one-to-one. Thus f is either increasing or decreasing. Now the inverse of f …
Concavity of intervals of $\sin x$. - Mathematics Stack Exchange
Jun 28, 2020 · The definition of a convex function,is: "An interval is called convex if the line segment between any two points on the graph of the function lies above or on the graph." …