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Solve equations witch contains absolute values

Solve equations witch contains absolute values

Solve equations witch contains absolute values

(OP)
Hi

(I apologise for my bad english!)

I have a question about mathcad. I have a equation loking something like this:

f(x)=N/A+M*(x-y)/W

witch I like to solve for f(x)=0
with other words,  I like to find the x for witch f=0

The problem is that the term (x-y) should be the absolute value and to me it looks like mathcad cant solv the equation using f solve,x-> when it contains absolute values

I then tried to rewrite the term like this:

squarrot( (x-y)^2)

 witch of corse is the same but I thought this way to write it maight help but NOP it dident. Matchad was unable to solve the equation so my question is:

How do i get Mathcad to solve equations witch contains absolute values?

RE: Solve equations witch contains absolute values

You can't, in general.  Such functions are highly discontinuous, and the only solution is to partition the problem and solve each partition separately.

TTFN

FAQ731-376: Eng-Tips.com Forum Policies

RE: Solve equations witch contains absolute values

(OP)
Hi again

Thanks for quick answers!

Unfortunately I cant tell whether zero, one or two of M, W, A and N will be negative. I guess I have to find another way too get around the problem.

Thanks anyway!

RE: Solve equations witch contains absolute values

Occupant has the solution but some times I find that using the assume directive helps too.   

Peter Nachtwey
Delta Computer Systems
http://www.deltamotion.com

 

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