@Mac Dude I can remember now. Thanks for your answer.

@Mac Dude If x=3 the expression cannot be simplified, because denominator is zero. So, I think that the procedure assumes x <> 3. What is my mistake?

Studying, I could see that using FunctionAdvisor(sin) is possible get information about part a) and b) of the question. How can I get only the identitie I need?

@Kitonum thank you for your answer. It was very useful. I learned several new commands. I voted your answer.

@Carl Love I changed a litle the code in order to get three tabulate plots.

for the last plot, I use the following code:

p3 := plot(`[]`~(f, g, t=~ [-10..-1.3, -0.7..10]),
    style= point, symbol= cross, symbolsize= 12, colour= coral, adaptive= true):

I would like print legend for last plot. The problem is that I havet to introduce two or I get an error. How can I correct that?

@Carl Love Hello, how are you? Thank you for your help. I tried your code, but I got error in title.

I tried this:

But I need points uniformly distributed in the plot.

@janhardo thank you for your help. I will read your answer inmediately.

@acer thank you for all your help, this forum is an excellent learning tool. I got what I wanted doing this:

DocumentTools:-Tabulate(widthmode = percentage, width = 75, [seq([seq(p[i], i = (j-1)*iquo(11,3) + 1..j*iquo(11,3))], j = 1..iquo(11,3)), [p[10], p[11]]]):

@acer if code this:

DocumentTools:-Tabulate(widthmode = percentage, width = 75, [seq([seq(p[i], i = (j-1)*iquo(11,3) + 1..j*iquo(11,3))], j = 1..iquo(11,3))]):

I get 9 plots and is possible to see an horizontal line between rows. I need to include the last two plots. Therefore I tried:

DocumentTools:-Tabulate(widthmode = percentage, width = 75, [seq([seq(p[i], i = (j-1)*iquo(11,3) + 1..j*iquo(11,3))], j = 1..iquo(11,3)+1)]):

However I got an error. I think it's because p[12] doesn't exists. How can I exclude this element?

@acer thank you for your help, I voted all your answer because I am learning a lot through these.

Supressed borders are no needed. In my sketch I tried to show position of plots only. I will try to be more clear in future question.

Greetings.

@Kitonum sure, I will change values. Thank you.

@Kitonum, very useful information. I unknow that one could use zip. That is shorter than for loop.

@tomleslie Thank you for your answer.
Sure, in future questions I will upload my worksheet. I am new with Maple, I started one week ago, so I need to learn a lot of important thinks. Thank you for this and all advices.

@acer thank you for help me. Your answer was very useful.