Help Solving Non-linear system of equations

[azzaz]

i m beginner in Mathcad , and i want solve a system of 05 Non-linear  equations simultaneously , to get the estimations of 05 parameters (a1,a2,B1,B2 ,P ) where ;

1)  "t' is a  vector with known values,

2)  r1=36 , r2=39 ,r=(r1+r2)=75 , n=100,Τ=0.7 

3) Guess values (a1=1,a2=1,B1=2,B2=1,P=0.5 )

the attached file contains the whole description

Any help ??

Thank you in advance.

[LucMeekes · Accepted solution]

I get an error trying to unpack your archive. Please use zip, it's standard in windows:

In Windows Explorer click with the right-mouse button on the mathcad file and select 'Send to' -> 'Compressed (zipped) folder'. The resulting .zip file can be attached.

Success!
Luc

[azzaz]

Thank you 

[-MFra-]

Hi,

[rgunwaldsen]

Nice. Can you post your Prime worksheet?

[Fred_Kohlhepp]

There are two files in the last zip, a version 11 and a version 15.  You should be able to convert either of those to Prime

[VladimirN]

Here it is, for Mathcad Prime 3.1 version.

[LucMeekes]

As it is, I cannot make an accurate guess of what you're trying to solve.

You've got some questions to answer (to yourself) and some rework to do. See attachment.

Don't hesitate to come back once you've expressed the problem more clearly.

Success!
Luc

[Fred_Kohlhepp]

Boy! 

I was able to open your file.  Attached is an archive with a version 15 and a version 11 resaved.

You've got r, beta, and alpha all as vectors.  With the ORIGIN default as zero, when you define r[1, Mathcad puts a zero in the first slot.  So your vectors all start with zero. . .  Then when you write your summations I don't think you're getting what you expect.

I reset the ORIGIN to 1.  (And had to rewrite the first two terms in g(t)) now all your equations compute and report two values each.

Last point:  Mathcad is primarily a NUMERIC processor--it's way more powerful with numeric than symbolic solutions.  My computer runs out of memory trying to achieve you symbolic solutions.  I suggest a numeric solve block  (Given . . .Find)

[LucMeekes]

Fred,

The attachment was a .rar initially, now changed to .zip.

And the OP uses Mcad 12 (at least, that's the version the sheet was saved in), so should be able to read your Mcad 11 file.

Luc

[-MFra-]

Hi!
I made some changes to your file to fit it to the  program . Each solution depends on the initial guesses that are very difficult to determine.