@leonardofernandez The problem with the file wrong.eps is that all decimal points have been written as "," (comma)..  You can fix it by replacing all occurrences of "," with ".".  I did, and was able to view the graphics.

No one has answered your question because it is not understandable as written.  You should clarify:

1. Why do you expect evalf(Int(f(y),y=-b..b)) be an integer?
2. What do you mean by g(sin(y) , cos(y) and exp(y))?
3. What is the point of the product a*10^354*(b*10^-356)?  Isn't it just a*b/100?

@Thomas Dean Here is how one activates an animation in Maple in general, not specific to this particular example:

1. Execute the code.
2. Wait for the animation's initial frame to appear.
3. Click on the image with the left mouse button.
4. Wait for the animation toolbar to apprar along the top edge of the worksheet.

See the help page on the topic "animation toolbar" to see what the various buttons do.

@Preben Alsholm Your sol3A is a very nice solution to a rather nasty problem.

@vv You may have obseerved that setting Digits := 40 yields the correct minumm.

Here are three circles.  What do you mean by "calculate the intersection between three circles"?

Aside:  You may have noticed that the equations shown in your post are little pictures of the contents of your Maple worksheet.  Those are not very helpful because I cannot copy and paste them in my worksheet, and certainly I am not motivated enough to type them myself.  In the future, consider inserting the text, not the image, of your equations when asking questions on MaplePrimes.

@Kitonum This one does the same thing and is simpler:

A:=[1,1]:  B:=[3,2]:
plot([A,B], color=red, thickness=3, view=[0..4, 0..3], scaling=constrained);

@Thomas Dean The name of the direcotory got mangled. Sorry.  Here it is again:

    maple2016/data/images/start  

The directory contains nearly 50 icons, 75x75 each, which should be a good size for desktop icons in my opinion, but you may use imagemagick to enlarge them, or if you want, I will be happy to do that for you.

Specifically, GettingStarted.png and HelpPages_default.png can be useful icons for your purposes. 

I used to use twm way back in the 1980s and early 90s, but I haven't used it in the recent years.  I recall that it was quite configurable. You may be able to coax it to use  icons of your choice for maple.

@Thomas Dean Icons and pretty much everything else on the Liniux desktop are handled by the Window Manager.  In the Linux world there are dozens of window managers, and what happens to your desktop is very much dependent on which one you are using.   Because of that, the meaning of "Icon" in your message is unclear.  It may be an icon in a pulll-down menu, an icon in the desktop's tool-bar (sometimes called "the panel"), or a stand-alone icon that is placed on your desktop.

I use the Xubuntu distribution of Linux.  The window manager is Xface.  Every window has a corresponding tiny icon in Xface's panel.  The icon is stretched/expanded to match the panel's width which is customizable.  Other managers may behave differently.  It's difficult to provide general advice.

That said, you may be interested in looking into

     maple2016/data/start

where you will find dozens of largish icons which you may be able to do something with.

@aryaneh You say that M.v is like v, but it is not.  In the M.v that you have calculated, all numbers have factors like 10^(-11) or 10^(-12) which are effectively zero because Maple uses only 10 digitis by default when calculating with floating point numbers.

To clean up the result by removing those numbers which are essentially zero, do:

    simplify(fnormal(M.v), zero);

This will show that M.v is actually the zero vector, as you expect.

On the other hand if you do:

    simplify(fnormal(v), zero);

you will see that the eigenvector v is non-zero, again as you expect.

If b, c, and x are positive, then how can x^2+b x + c be zero?

@aryaneh The solution is simpler than what you have shown.  See the attached worksheet for details.

doit.mw

I know nothing about fractional differential equation but you may find the following useful:

    http://www.sciencedirect.com/science/article/pii/S0377042712000064

Example 12 there is very much like your system of equations.

@fereydoon_shekofte Your formula is correct.  It agrees with what I had written in the paragraph under the heading Conclusion in the worksheet daylight3.mw which I had posted earlier. In your formula tan(tilt) appears in the denominator while in mine it appears in the numerator because you measure the tilt angle relative to the equator while I measure it relative to the north pole.

@vv Thanks for the information about Explore and your modified code.  I rarely think of using Explore but I see that in this case it can be quite helpful, especially when memory is tight.

As to your suggested parameter ranges to Explore, I would change lambda=0..2*Pi to lambda=-Pi/2...Pi/2 because that's how latitude is customarily measured.  Also a practical range to the tilt angle would be tau=0..Pi/2.  But these are only minor considerations.