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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

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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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