>restart:

>ans:=401/2 - 1880/(3*Pi); 

>[numer(op(1,ans)),denom(op(1,ans)),numer(op(2,ans)),op(1,denom(op(2,ans)))];

[401, 2, -1880, 3]

Take a look at the help files for the assign command as well.

>?assign

Try this thread from a previous posting:

beta.mapleprimes.com/blog/johns/symbolic-integration-over-a-region 

This link from Acer's blog might be of use to you.

www.mapleprimes.com/blog/acer/quadraturefastbesselj0highparametervalues 

What is the problem that you encountered with the code that you posted?  I tried it with the following lines added to the top of the worksheet and it seemed to work just fine.  I'm not sure if that is what you intended.

>with(DEtools): with(plots):

Are you looking for something other that what was plotted?

App center link here:

www.maplesoft.com/applications/app_center_view.aspx

Download and open the zip file.  Open the worksheet called femPackageCode.mws

Follow the instructions for creating the library that are in the worksheet.

Start by looking up the definition for percent change.  You will get a formula and and explanation.  Try to understand the explanation first.  Blindly plugging numbers into formulas does not teach you anything.  Do it by hand first, and then try it in Maple.  That way you can use Maple to verify your answer.

www.robertniles.com/stats/percent.shtml 

In Maple, you would do it like this;

>percent_change:=100*((180-135)/135);

>evalf(percent_change);

At the beginning of  your worksheet, add the following line;

>with(plots):

Then retry and see what happens.

Try this:  Replace your plot3d call with the lines below and see if it does what you expect.

>plot3d(f, 0..20, 0..70, style=patch,color=myProc); 

or

>plot3d(f, 0..20, 0..70, style=patch,color=f);

Check out this link as well.

www.mapleprimes.com/forum/plot3d-and-color

Can you upload your Maple 10 worksheet.  I do not have Maple 10 on my laptop, but I would like to try it with Maple 11.  Does it matter which interface you use?  Does classic do the same thing as standard? 

See John Fredsteds blog below:

www.mapleprimes.com/blog/john-fredsted/plots-of-twisted-ribbons

Take a look at the help pages for Student[Calculus1][DerivativePlot].  At the Maple prompt, type the following and hit the enter key.

?Student[Calculus1][DerivativePlot]

There are examples there that you can follow by cutting and pasting the code into your own worksheet.

The Student[Calculus] package also supports root finding over a range.  Similar to what Prof. Israel suggested above, you can try the following:

>restart: with(Student[Calculus1]):
>Roots(x*cos(x) = sin(x), -10..10,numeric );

[-7.725251837, -4.493409458, 0., 4.493409458, 7.725251837]

>Roots(tan(x)-x, -10..10,numeric );

[-7.725251837, -4.493409458, 0., 4.493409458, 7.725251837]

Take a look at the LibraryTools package.  It needs to be loaded in order to use it.  

>?LibraryTools

Your link above did not post well.  I recreated it below so others can view it more easily.

Download 221_Maple_Primes_3_08.mws
View file details

The command is case sensitive.  So VolumeofRevolution is not the same as VolumeOfRevolution.  The function is part of the Student package, so in order to use it you have to load the package.

>with(Student[Calculus1]):

See file below for details.

Download 221_VolumeOfRevolution.mws
View file details

The attached file has two ways of doing this.

Download 221_dataplot.mws
View file details