A function is said to be concave on an interval if, for any points and in , the
function is Convex on that interval. If the second Derivative of

on an open interval (where is the second Derivative), then is concave up on the interval. If

on the interval, then is concave down on it.

**References**

Gradshteyn, I. S. and Ryzhik, I. M. *Tables of Integrals, Series, and Products, 5th ed.* San Diego, CA:
Academic Press, p. 1100, 1980.

© 1996-9

1999-05-26