## How to simplify it?...

Hi,

I am a newbie in Maple. I have the following code

with(LinearAlgebra):
w := (2*Pi)/14
v := Vector([1, sin(w*t), cos(w*t)])
simplify(sum(v . (Transpose(v)), t = k .. k + 13))

Even with some less advanced CAS I get that the result is a diagonal matrix with constant elements. However, I failed to properly tune the simplify command to get such a result. What I am doing wrong?

## Selecting and copying...

I have two questions:

1) How can I select only parts of an equation in a Maple Workbook? E.g. I have

4*x^2*(1 + x)^2*(x^2 + 6*x + 1)

and I want to select the text between the first "2" and the "6", but Maple always extends the selection to include the complete bracket. This is very annoying :)

2) How can I copy text from a maplesoft page into a workbook. E.g. I'm looking at

and I would like to select and copy some of the shown examples so that I can use them.

## hypergeometricsols bug...

I believe I have found a bug or unintended behaviour:

The following second-order DE:

mplinput := ((x^4 + 4*x^3 + 10*x^2 + 4*x + 1)*diff(y(x), [x \$ 0]))/(4*x^2*(1 + x)^2*(x^2 + 6*x + 1)) + 2*(x^2 + 5*x + 2)*diff(y(x), [x \$ 1])/((1 + x)*(x^2 + 6*x + 1)) + diff(y(x), [x \$ 2])=0:

can be solved by

with(DEtools):
hypergeometricsols(mplinput);

in terms of hypergeom functions. However,

dsolve(mplinput, [hypergeometricsols]);

does not find a solution, although it is supposed to use the same algorithm. One can trace this back to the sub-algorithm 'DEtools/2F1: --- find_2f1 ---' which is apparantly used by hypergeometricsols, but not by dsolve.

Another thing is that dsolve(mplinput, [hypergeometricsols]) in fact works in Maple2020, but does not in Maple2021 and Maple2022.

## Syrup installation seems not to work...

Hi,

I installed syrup within Maple 2022 according to the procedure described in syrup's README file. The installation seems to run normally. After that I restarted Maple. When I now enter

with(Syrup);

it shows

[Draw, Library, Print, Solve, ToModelica, ToSpice, Version]

[deindex, makecheckttable, printdeck, reindex, syrup]

as described in the application center: https://www.maplesoft.com/applications/Preview.aspx?id=4680

Also the example which is decribed there doesn't work:

syrup(divider, dc, 'curr');

delivers no result.

I'm working on Windows 10 64 bit.

Could it be that syrup is not yet prepared for Maple 2022, as it seems not to be updated for a long time? Or is the description in the application center not up to date?

Best regards,

Michael

## Error:-'IsTrigProc'[resolved]...

Hi,all

I am new in Maple,when I execute the "InversePlot" command ,all functions were correct except for exp(x), error occurs as follows, can anyone tell me what mistake I took?

restart;
with(Student[Calculus1]);

InversePlot(exp(x), -1 .. 1);
Error, (in Student:-Calculus1:-InversePlot) module does not export `IsTrigProc`

Tks for all you guys.

I have uninstall Maple and deleted the installed directory ,clear the register,reinstall Maple 2022, now all works well.

I think the problem is I installed Maple 2022 in the old directory of 2021for keeping my configuration,this caused much unexpected problem

## How to type a vector symbol in Maple...

I want to create a variable that is made up of a letter and an arrow on top. How to do that?

Also, how can I create a variable that is bold? I tried to type it as bold and then assign. But when I hit return it returns a normal symbol.

How to distinguish between a scalar variable and a vector variable in Maple?

## How to solve a differential equation in Maple?...

Hi,

I want to solve a differential equation and plot the particle densities versus the distance.

How can I do this in Maple?

DE.mw

Sincerely

## How can I make maple to show me the Euclidean algo...

Suppose I want to calculate gcd(g(x),f(x))=a(x)f(x)+b(x)g(x) for two polynomial, i.e finding the RHS representation of the gcd, then how to implement this in maple?

I know of the command GCD(f(x),g(x)) but how to find the RHS representation?

Thanks!

## How to get a better italic D output?...

Many formulas use a capital D to define parameters. A popular example is the second moment of area "I" of a tube. In Maple we get

Both I and D are protected symbols in Maple and are therefore printed in roman. With the "local" command, I and D can be used as unprotected symbols. However, only the unprotected "I" is printed in italic (like other symbols or names do). D is still printed in roman, which spoils Maple's excellent printout (a bit).

I hope this inconsistency can be improved one day. For the time being, I am looking for better alternatives than my workaround with a fat white space in the attachment. Are there better workarounds?

Italic_I_and_D.mw

## An integral done by Maple 11 but not by Maple 2021...

primes_integrale_exp.mwThe integral in x of

exp(-sqrt(x^2 + c))

was done by Maple 11 but return unevaluated in Maple 2021,

see attached worksheet

## Try to solve an integral equation, Maple fsolve ti...

I am trying to solve the equation in the attached Maple file, but Maple cannot return a result.

 (1)

 (2)

say the f(x) is a Beta with parameters alpha and beta

 (3)

 (4)

 (5)

 (6)

## How to limit the number of cores / threads used by...

On a shared cluster with 32 CPU cores, how do I limit Maple (called from the Linux command line) to use only 8 cores? (Certain built-in operations in Maple are parallelized by default.)

## Pell Fermat equation...

I try to sove the equation x^2-10*y^2=9 with tne procedure :
genpellsolve := proc(D::posint, N::integer)
local t, u, L1, L2, sols, x, y;
if type(sqrt(D), integer) then error "D must be a nonsquare integer"; end
if; t, u := pellsolve(D); if 0 < N then L1 := 0;
L2 := floor(sqrt(1/2*N*(t - 1)/D)); elif N < 0 then L1 := ceil(sqrt(-N/D));
L2 := floor(sqrt(-1/2*N*(t + 1)/D)); else return {[0, 0]}; end if;
sols := {}; for y from L1 to L2 do x := sqrt(N + D*y^2);
if type(x, integer) then sols := sols union {[x, y]};
if (x^2 + D*y^2) mod N <> 0 or (2*x*y) mod N <> 0 then sols := sols union {[-x, y]};
end if;
end if;
end do;  return sols;
end proc:
This procedudure fails; I don't see why. Thank you for your help.