@acer   

here is Andre Heck's reply to me:

Dear Ali,

On https://staff.fnwi.uva.nl/a.j.p.heck/Maplebook/answers3.html
the link  to the Windows zip-archive works and provides worksheets with all answers to exercises

on https://staff.fnwi.uva.nl/a.j.p.heck/Maplebook/sheets3.html
the link  to the Windows zip-archive works and provides worksheets with all examples in the book

some codes do not run maple 2018.. esp. chp 17

@Ali Guzel  

to say that I have Maple V licence too from a book...

Though Version V runs on this computer, Maple 7 does not save or open a worksheet.

Cheers 

@acer 

Thanks Acer for quick reply.

Andre Heck uses Maple 8 for example.. There are others as well

@Robert Israel 

This is a classic of OR problem...  Dr. Robert does it without decomposition... Bravo

@adel-00 

like this:

        simplify(solve(K1=0,R,explicit));

Cplex is very good at binary/integer problems. Academic version available

@acer 

I see Sir, there are things that I should learn from you... Thanks

Cheers to Dr. Venkat Subramanian and Dr. Acer

This one is the best !

I still think that MapleSoft should update

        use RealDomain in solve(eq,x,explicit) end use   ## lacking some of the roots

this!!! 

Acknowledgement: The procedure allroots is a modification of one written by:

Robert Israel, Department of Mathematics, University of British Columbia, Vancouver, BC, Canada V6T 1Z2 

On the link below allroots worksheet seem to work robustly..

http://www.peterstone.name/Maplepgs/roots.html

I still could not understand why

use RealDomain in solve(eq,x,explicit) end use   ## lacking some of the roots

gives partial answer intead of 22 roots as I showed at the top of this discussion...

@Carl Love 

@Axel Vogt 

@Ali Guzel  

I am using maple 2018 also have maple 2021

@Axel Vogt