AFAIK, pdsolve(..., numeric) can only handle PDE systems with 2 differentiation variables. You have X, R, and t.

Here are two ways:

subsindets(expr, specindex(a), x-> b[op(x)])

Or, if you know that all the a's that you want have exactly 1 index:

subsindets(expr, a[anything], x-> b[op(x)])

How do you expect it to react when you give it a y-range that's out-of-bounds (into complex numbers) for the function? Narrow the y-range to -1.53..1.53.

The command FunctionAdvisor will give you a huge amount of information about a special function. Try

FunctionAdvisor(Ei[1](x)).

The notations Ei[a](x) and Ei(a, x) seem to be used interchangeably, and

 Ei(x) = Ei(0, x) = Ei[0](x) = exp(-x)/x.

Here's another way, just to show the possibilities. I often prefer index-free methods, which let me treat matrices and vectors as whole mathematical objects in their own right rather than "poking inside" them.

I construct a matrix of products of powers of X and Y by taking the outer product of a vector of powers of X and a vector of powers of Y. Then I take the elementwise product of that with m. Then use add, which can be used without indices.

(X,Y):= (2,3):  (r,c):= op(1, m) -~ 1:
add(<X^~($0..r)>.<Y^~($0..c)>^%T *~ m);
                            -11.518

I will readily admit that the above, done on a large scale, will increase your garbage collection time. 

I've done this with respect to your Solusi5, but it can be done for any of your plots.

Colors:= [red, blue, green]:
F:= [A, l, S](t):  tF:= [t, F[]]:
plots:-display(
    plots:-odeplot(
        Solusi5, `[]`~(t, F), t= 0..5, numpoints= 1000,
        color= Colors, legend= [A5, I5, S5]
    ),
    annotation= (typeset @ xcoordinate)(
        proc(t) option remember; uses T= Typesetting;
            (T:-mtable @ op @ (T:-mtr @ T:-mtd @ T:-mtext)~)(
                sprintf~("%a = %a", tF, evalf[5](eval(tF, Solusi5(t)))),
                mathcolor=~ [black, Colors[]], mathsize= 14
            )
        end proc
    )
);

This will initially appear to be a plot just like your version. The difference will become apparent when you drag your mouse over the curves. Instead of the usual box with the x and y coordinates, you will get a box with a column of numbers. The top line gives the value of t at the cursor; the next 3 lines give the values of A, l, and S for that value of t. Each of these lines is the same color as its corresponding curve.

There are no Maple help pages for the Typesetting package operators that I used: mtable, mtr, mtd, mtext, mathsize, and mathcolor. These are MathML operators which you can find some help for on many independent webpages; then you need to convert them to Maple syntax. There are Maple help pages for typeset and annotation, which aren't part of the Typesetting package. The definition of xcoordinate is on the annotation help page. The sprintf is a standard Maple command, and very similar to the sprintf in C and other languages. The @ is the function composition operator (help page ?@). The ~ is the elementwise operator (help page ?operators,elementwise). The `[]` is the list-building operator in prefix form (a tiny amount of help at ?use). 

Let me know if you'd like this format changed in any way.

Like this:

select(hastype, A01 + _z, specfunc(tanh))

Edit: I added + _z to avoid the problem that acer mentioned.

This quickly returns a fairly simple elliptic expression:

int(1/sqrt((a-t)*(t-b)*(t-c)*(t-d)), t= b..a) assuming d<c, c<b, b<a;

You shouldn't make assumptions about a variable of integration, t in this case; it's done automatically.

The easiest way to get the nontrivial solution is

solve({eq||(1..4)}, {DC, tau, ton, T})

Since there's only one solution, assumptions can't help.

Do

eval(A1, exp= cos)

It seems like the motivation for your Question is doing some preparation for solving your BVP by the shooting method. Acer's implicitplot shows that there are likely 4 solutions. Maple does have a direct numeric solver for BVPs, but it's difficult to use when there are multiple solutions. Shooting works well and fast in this case. The entire worksheet below executes on my computer in less than 1 second, generating plots of y(x) and y'(x) for all 4 solutions.

Download Shooting_method.mw

Like this:

restart;
mysphere:= (x - a)^2 + (y - b)^2 + (z - c)^2 - 10^2 = 0;
L:= [seq](seq(seq(`if`(igcd(a,b,c)=1, mysphere, NULL), a= 1..5), b= 1..5), c= 1..5);
 

The command to merge the iterated exponents is combine. For example, starting with the original W, you could do

combine(convert(W, exp));

For future Questions, please note that uploaded worksheets are much more useful to us than uploaded screenshots. In this particular case, the Question is simple enough that a photo was sufficient, but that's rarely the case.

combine can also work directly on your hyperbolic trig functions, so this produces an equivalent result:

convert(combine(W), exp);

I know that this Answer is not exactly what you're asking for, but you might find it useful anyway; and it's what I use personally. Any plot in Maple is simply a data structure that can be assigned to a variable. (In formal computer science, they would be called "first-class data structures".) The assigning can be done either before or after the plot is produced.

Before:
MyPlot:= plot(x^2, x= -2..2);

After:
plot3d(x*y, x= -1..1, y= -1..1);

... plot output omitted ...

MyPlot2:= %:

This can be done with any command that produces a plot or plots as its formal output (i.e., return value); they needn't be from the specific plot or plot3d command. Like any first-class data structure, the assignment can be done can be done regardless of whether the plot appears on screen.

I've had a similar (although not identical) thing happen several times (although not with Maple 2023). In my case, some math symbols changed also: for example, + became C and - became K. 

In my case, the problem could be corrected by saving and closing the worksheet, then closing the entire Maple session, then restarting Maple and the worksheet.

The problem was only with the display of the worksheets, not their underlying content (which remained unchanged). Once it affected one of my open worksheets, it affected all of my open worksheets. And, I do tend to keep worksheets open for many days, sometimes weeks.

Let me know if opening and closing corrects the problem for you.