is the reason for Image result?

Download cos

Are there commands in Maple to find the order and degree of an ODE?  Searching help I could not find anything so far.

For an example, given 

restart;
ode:=(1+diff(y(x),x)^2)^(3/2)=diff(y(x),x$2)

I want the command to return 2 for the order of the ODE and degree is also 2 in this case.

I looked at DEtools package and googled. I am sure Maple have build in commands to do this without me having to parse the ODE myself to find out.

so i just went from a really old version of maple to a the newest one maple 2019 and at first glance it doesn't seem to work correctly please take a look at the picture maybe there is a toggle i missed or something of the sorts thanks you for your time 

I have a tough integral I'm trying to solve (see attatched code). Maple seems to be able to compute it if I instruct it to integrate by parts, however the solutions don't make sense. For example, if I differentiate the result I expect to get my original integrand, but I do not. Furthermore, depending on which function you choose as 'u' and which as 'dv' when integrating by parts yields different results.

071319_Integral.mw

The attatched code has four examples:

1) Definite integration by parts

2) Indefinite integration by parts

3) Indefinite integration by parts, alternate choice of 'u'

4) Definite integration by parts, alternate choice of 'u'

and after each indefinite integration, I differentiate the result to compare with the orginal integrand.

What is going on here?

Hi,
I would like to trace periodic functions. I saw that this was possible with the old 'FourierSeries' package with the "Rept" command. How to reproduce the same thing in the Maple 19 environment? Thank you

fs_examples.mw

fyi, there seems to be a problem here. Maple 2019, Physics version 395 on windows 10.

The solution given to this wave PDE by Maple as sum that starts from zero, has "n" in the denominator. When n=0, this gives division by zero.  Is this a bug?

Download bug_july_11_2019.mw

 I'm confused as to why Maple can't perform a certain integral for me. Please see my attached code - it get's stuck on the last step.

070919_ThetaIntegral.mw

Does anyone know how collect zero epsilon coefficient from follow expression?

coeff_test.mw

Is it possible?

Thank you!

I am able to generate random polynomials with non-zero coefficents, and define sets of all the positive divisors of the leading coefficient and the constant terms. My question is this, how may I apply the rational zeros theorem to generate the set of all possible rational zeros of the polynomial. I basically need to form all the possible quotients (positive and negative) with numerator in one set and denominator in the other set, ignoring duplicates. The attached worksheet has what I've done so far.rational_zeros.mw
 

Download rational_zeros.mw

The command eval allows to simplify a complicated expression

in a more compact form for a later output in LATEX

In the example which follows I was able to insert A and B but non C in the expression.

There is already a post on this kind of topic but I failed to understand the details.

Perhaps a Maple worksheet of answer on this topic  would be useful !

bye Lorenzo
 

Download maple_primes_eval.mw

Hi

I've just installed Maple latest + MapleSim with the license provided by my university (I use VPN with a secure key to remotely access server license. Everything works fine, except for the context menu. It seems that the context menu module is missing! I tried uninstalling and reinstalling, but did not help.

I went back to the campus and checked Maple installation on computers there, and this problem is absent (context menu is working fine).

I can only use the context menu toolbar on the right... but this is not very convenient. 

What could be the problem? See the attached image.

Thanks

---------------------

Hi!

How to calculate  a value in MAPLE:

My code:

evalf(eval(diff(n*Zeta(n, 3), n), n = 3)); give me:

#-0.3740436824 + 3.*eval(diff(Zeta(n, 3), n), {n = 3}) ,it should be only:-0.3740436824

OR:

fdiff(n*Zeta(n, 3), [n], n = 3);

#fdiff(n -> n*Zeta(n, 3), [1], [3]) ???

It's a Bug  or (As Designed / Not a Bug) ?

Thanks in advance.

Mathematica code:

D[n*Derivative[n][Zeta][3], n] /. n -> 3 // N;

(* -0.374044*)

I just used Maple for the first time to find the roots of an equation, the problem they give me imaginary solutions every time I put a (ln); even for ln (1) it proposes me -265.745524189222 + 0.785398163397448 * I as a solution. Could you help me to solve this problem?

Why doesn't

f:=ln(s + 2)^2 + 2*polylog(2, -1 - s) + 2*polylog(2, (1 + s)/(s + 2))

simplify to zero assuming s>0?

I solved this PDE by hand to verify Maple's solution. I think Maple solution is wrong. This PDE is the heat PDE on a bar (1D) with boundary coditions on both ends are function of time and zero initial conditions.

unassign('A,B,x,t,L,k,f');
pde := diff(u(x,t),t)= diff(u(x,t),x$2):
bc := u(0, t) = A(t), u(1, t) = B(t):
ic := u(x, 0) = 0:
sol1:=pdsolve([pde, ic, bc], u(x, t));

#now try when A(t)=sin(t),B(t)=t, use 20 terms for the sum
sol2:=simplify(subs([infinity=20,B(tau)=tau,A(tau)=sin(tau),A(0)=0,B(0)=0,A(t)=sin(t),B(t)=t],sol1)):
sol3:=simplify(value(subs(t=1,sol2))):
evalf(subs(x=0.5,sol3))

Also doing pdetest(sol1,pde); on the above solution does ot return zero as expected.

To verify more, I solved the same PDE again, but now using an explicit values for the boundary conditions A(t), B(t). Using A(t)=sin(t), B(t)=t. Then found the value again of the solution u at x=0.5 and t=1 like in the above, and it gives different value:

unassign('A,B,x,t,L,k,f');
pde := diff(u(x,t),t)= diff(u(x,t),x$2):
bc := u(0, t) = sin(t), u(1, t) = t:
ic := u(x, 0) = 0:
sol4:=pdsolve([pde, ic, bc], u(x, t));
sol5:=simplify(subs(infinity=20,sol4)):
sol6:=simplify(value(subs(t=1,sol5))):
evalf(subs(x=0.5,sol6))

Then I typed my hand solution into Maple and for the same values x=0.5, t=1 and same number of terms, I also get the same value 0.819. 

I do not see at all where the function sin integral should come into play in this solution. 

Could some Maple expert please check to see what is going on with this solution to Maple? 

Using Maple 2019.1 and Physics version 370