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 Author Comment/Response Karin 08/30/99 07:58am I have a function f(x) that I want to minimize. I therefore take the derivative of f with respect to x, set it to 0 and solve for x. Solve[D[f,x]==0,x] Say that gives me xopt=1/y+1 where y is a (symbolic) constant. Now I need to make sure that xopt is within the boundaries of possible values of x. Say that xy<1 is the only constraint I have. In version 3 I can't use InequalitySolve[xy<1,x] since xy<1 is not a ''formula constructed with univariate polynomial equations and inequalities in x''. I assume that is because Mathematica doesn't know if y is less than or greater than 0. My question is therefore would Mathematica 4 be able to solve this problem for me given that I know y is positive? Maybe with InequalitySolve[xy<1,y>0,x] i.e. with the added assumption that y is greater than 0? Is there another way of solving this problem? (Solve[xy==1,x] doesn't help me since I only get the boundary valuie x=1/y as ananswer. I still don't know if 1/y+1 is inside the boundaries or not...) Thanks for any help, Karin URL: ,

 Subject (listing for 'can version 4 solve this?') Author Date Posted can version 4 solve this? Karin 08/30/99 07:58am minimizing objective function with constraints ... P.J. Hinton 08/31/99 05:57am Re: minimizing objective function with constrai... Karin Hogstedt 09/01/99 6:53pm Re: minimizing objective function with constrai... P.J. Hinton 09/09/99 09:38am
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