inequalities

*Subject*: [mg2465] inequalities*From*: <rizzi at img.fr>*Date*: Mon, 13 Nov 1995 03:27:15 GMT*Approved*: usenet@wri.com*Distribution*: local*Newsgroups*: wri.mathgroup*Organization*: C.I.C.G. , Grenoble*Sender*: daemon at wri.com ( )

Let expr be an expression which depends on a and b. How can I check the sign of expr (e.g. positive) when a and b satisfy some inequality constraints? Example: f=(-9 - 23*c4 - 19*c4^2 - 5*c4^3 + 9*nu + 21*c4*nu + 15*c4^2*nu) Check the sign of f when -1 < c4 < Infinity and 0<= nu <= 0.5 Thanks in advance, Egidio rizzi at geo2.img.fr