Unanswered Questions

Is opening recent documents not working when no wo...

Asked by: C_R 3457

10 hours ago

0 1

With the new ribbon interface (and startup-page disabled) I need to open a new worksheet to make opening files by the recent document menu work.

Can someone reproduce this?

Issue in Determining Optimal KKT Multiplier (μ₁) i...

Asked by: Andiguys 85

19 hours ago

0 0

I am attempting to solve an optimization problem using the Karush–Kuhn–Tucker (KKT) conditions, where the objective function is to be maximized subject to a constraint that may or may not be binding. However, when solving the system, the KKT multiplier (μ1) consistently evaluates to zero, even when the constraint appears to be active. I am unable to determine the optimal value of μ1 and seek guidance on how to obtain the optimal values of Pn, Pr, and w, as well as the correct condition for μ1.

>

with(Optimization); with(plots); with(LinearAlgebra)

>

(1)

>

`π_m` := proc (Pn, Pr, w) options operator, arrow; (Pn-Cn)*(1-(Pn-Pr)/(1-delta))+(Pr-w-Crm)*alpha*(1/2+(1/2)*((Cr*Pn*i2-Cr*Pn*tau-Cr*Pr*i2+Cr*Pr*tau+Cr*delta*i2-Cr*delta*tau+2*delta*i2*tau-2*delta*tau^2+2*w*tau*delta-Cr*i2+Cr*tau-2*i2*tau+2*tau^2-2*w*tau)/(Cr*Pn-Cr*Pr+Cr*delta+4*tau*delta-Cr-4*tau)-i2)/tau)*(1-(Pn-Pr)/(1-delta))-Ce*rho0*(1-(Pn-Pr)/(1-delta)) end proc

proc (Pn, Pr, w) options operator, arrow; (Pn-Cn)*(1-(Pn-Pr)/(1-delta))+(Pr-w-Crm)*alpha*(1/2+(1/2)*((Cr*Pn*i2-Cr*Pn*tau-Cr*Pr*i2+Cr*Pr*tau+Cr*delta*i2-Cr*delta*tau+2*delta*i2*tau-2*delta*tau^2+2*w*tau*delta-Cr*i2+Cr*tau-2*i2*tau+2*tau^2-2*w*tau)/(Cr*Pn-Cr*Pr+Cr*delta+4*tau*delta-Cr-4*tau)-i2)/tau)*(1-(Pn-Pr)/(1-delta))-Ce*rho0*(1-(Pn-Pr)/(1-delta)) end proc

(2)

>

C1 := (((Cr+4*tau)*delta-4*tau+(Pn-Pr-1)*Cr)*rho0+(delta-1)*(i2-tau))/(delta-1) <= w

(3)

>

>	# No equality constraints f[1] := (Pn,Pr,w) -> (((Cr + 4tau)delta - 4tau + (Pn - Pr - 1)Cr)rho0 + (delta - 1)(i2 - tau))/(delta - 1)-w:

>	# Lagrangian (we want to maximize `π_m` so to minimize -`π_m` L := -`π_m`(Pn,Pr,w) + add(f[i](Pn,Pr,w)*mu[i], i=1):

>	dLdPn := collect(diff(L, Pn), [Pn]): dLdPr := collect(diff(L, w), [Pr]): dLdw := collect(diff(L, w), [w]):

>

KKT_conditions := [
                    seq(mu[i] >= 0, i=1),         # Dual feasibility conditions
                    dLdPn = 0,
dLdPr = 0,
dLdw = 0,                     # Stationarity condition
                    seq(``(f[i](Pn,Pr,w)) <= 0, i=1), # Primal feasibility conditions
                    add(mu[i]*f[i](Pn,Pr,w) = 0, i=1) # Complementary slackness
                  ]:

print~(KKT_conditions):

alpha*(1/2+(1/2)*((Cr*Pn*i2-Cr*Pn*tau-Cr*Pr*i2+Cr*Pr*tau+Cr*delta*i2-Cr*delta*tau+2*delta*i2*tau-2*delta*tau^2+2*delta*tau*w-Cr*i2+Cr*tau-2*i2*tau+2*tau^2-2*tau*w)/(Cr*Pn-Cr*Pr+Cr*delta+4*delta*tau-Cr-4*tau)-i2)/tau)*(1-(Pn-Pr)/(1-delta))-(1/2)*(Pr-w-Crm)*alpha*(2*delta*tau-2*tau)*(1-(Pn-Pr)/(1-delta))/((Cr*Pn-Cr*Pr+Cr*delta+4*delta*tau-Cr-4*tau)*tau)-mu[1] = 0

(4)

>

Download Solve_mu1.mw

How to call maple in Lazarus Pascal ...

Asked by: sedsil66 0

October 17 2025

0 1

I have a Pascal program. I want to use a Maple program inside the Pascal program when calling it each time. I dont know how to interact Maple with Pascal. For this, could you give me over a small program? Yours Sincerely

How Maple 2023 displays new results with old resul...

Asked by: alamir 10

October 17 2025

0 0

How Maple 2023 displays new results with old results together

How to change the tab key spacing?...

Asked by: NeillSmith 187

October 13 2025

0 0

I use the tab key to control the formatting of lists.

On my computer the tab key spacing under Maple 2025 is a little more than one inch which is too much. I have been through the Maple Help and cannot find how to change the tab key spacing.

Any help will be greatly appreciated.

My current account email is dead so I can only view answers here.

Solving pde system for H-shaped and square domains...

Asked by: Suryakanth 25

October 10 2025

1 7

Hello everyone,

I am working on reproducing Fig. 12 (Isotherms) and Fig. 13 (Streamlines) from the attached paper, cacity_paper_work.pdf which deals with natural convection of GO–MgO/silicone oil hybrid nanofluid inside square and H-shaped cavities under a periodic magnetic field.

Equations (9–11) in the paper describe the steady-state 2D flow and heat transfer in terms of u(x,y), v(x,y), and θ(x,y). I have already set up the full PDE system, parameters, and boundary conditions (BCs) in Maple.

Now, iusing pdsolve(..., numeric, method=fd),

Solve these equations for both square and H-shaped cavities using the given ICs and BCs, and

Generate Isotherm and Streamline plots (similar to Figs. 12 and 13 in the paper).

I have attached:

The PDF (showing equations and figures), and

My Maple worksheet containing the PDE definitions and parameters.

I would really appreciate guidance on:

Whether dsolve can be used effectively for this PDE system,

How to define the BCs correctly for the H-shaped cavity (especially the partially heated wall, θ=1 for 0.4 < y < 0.6), and

How to extract and plot the temperature (θ) and streamfunction (ψ) fields similar to the paper’s plots.

error_in_cavity_work.mw

physics update, write access...

Asked by: Jean-Michel 40

October 06 2025

0 2

Hello,

I have full access on .../.../version.txt but Maple tells me I have no write access...

Sorry for the previous post, thank you.

If I try with the install command I get the same error.

Kind regards to all

Jean-Michel

PS: have a look on the two inserted screenshots

Why dsolve do not resolve constant of integration ...

Asked by: nm 11503

October 04 2025

0 3

Given an ode with IC. When solution is explicit, Maple resolves the constant of integration as expected and returns solution with no c__1 in it.

But when asked for implicit solution, also with same IC, it now returns solution with c__1 still there.

Is this by design or a bug? Should not constant of integration be resolved using IC in both cases? If unable to solve for c__1 because solution is implicit, should it then not return solution all?

Does this happen in earlier versions of Maple?

>

restart;

>	interface(version);

>	Physics:-Version();

>	SupportTools:-Version();

>

restart;

>	IC:=D(y)(0)=0; ode:=diff(y(x),x)^2+x*y(x)=0: sol:=dsolve([ode,IC]);

>	sol:=dsolve(ode,'implicit');

y(x) = 0, -x^2/((x^3+9*y(x))*(x^2+3*(-x*y(x))^(1/2)))+3*(-x*y(x))^(1/2)/((x^3+9*y(x))*(x^2+3*(-x*y(x))^(1/2)))-c__1 = 0, x^2/((x^3+9*y(x))*(-x^2+3*(-x*y(x))^(1/2)))+3*(-x*y(x))^(1/2)/((x^3+9*y(x))*(-x^2+3*(-x*y(x))^(1/2)))-c__1 = 0

>	#WHY did not resolve constant of integration here?? sol:=dsolve([ode,IC],'implicit');

x^2/((x^3+9*y(x))*(-x^2+3*(-x*y(x))^(1/2)))+3*(-x*y(x))^(1/2)/((x^3+9*y(x))*(-x^2+3*(-x*y(x))^(1/2)))-c__1 = 0, -x^2/((x^3+9*y(x))*(x^2+3*(-x*y(x))^(1/2)))+3*(-x*y(x))^(1/2)/((x^3+9*y(x))*(x^2+3*(-x*y(x))^(1/2)))-c__1 = 0, y(x) = 0

>

Download why_C_still_in_solution_maple_2025_1_oct_4_2025.mw

Maple Flow 2025 Table of Contents auto generation...

Asked by: Shaggy 25

October 03 2025

0 5

Hello, I have a Maple Flow worksheet that is formatted with a basic style template using headings and sections so that I can auto generate the table of contents. All of the numbered sections are in order, top-to-bottom in the worksheet. However, when Maple Flow auto generates the table of contents, it consistently gets the sections out of order - see a screenshot below - note Section 2 is at the end of the table of contents. The page numbers appear to be correct, but the physical placement of Section 2 is not.

If anybody has encountered this problem in Maple Flow, I would appreciate some suggestions.

Thanks

why PDEtools:-Solve crashes Maple server?...

Asked by: nm 11503

October 03 2025

0 0

For some reason, solve() works Ok, but PDEtools:-Solve causes kernel crash.

Attached worksheet.

Anyone knows why and can someone try to reproduce this? I am using Linux CaucyOS (arch linux based) and Maple 2025.1

>	interface(version);

>	Physics:-Version();

>	SupportTools:-Version();

>

restart;

>

eq:=[-3/2*_C6^2+4*(60588*_C6^3+6659802*_C6^2-7113718800*_C6+168667884119)/(40392*_C6-971364)-1/8*(-6*_C6+1)^2-4*(1406664*_C6^2-1186536946*_C6+27728821045)/(26928*_C6-647576)+5*_C6-125/6+9*(-1/24*(-6*_C6+16)^2-4*(1406664*_C6^2-1186536946*_C6+27728821045)/(26928*_C6-647576)+(60588*_C6^3+6659802*_C6^2-7113718800*_C6+168667884119)/(40392*_C6-971364))*(-49/2+_C6) = 4, -1/24*(-6*_C6+49)^2+191*(1406664*_C6^2-1186536946*_C6+27728821045)/(26928*_C6-647576)-(60588*_C6^3+6659802*_C6^2-7113718800*_C6+168667884119)/(40392*_C6-971364)+1/12*(-6*_C6+9801)^2 = 0];
Cs:={_C6};

${_C6}$

>	solve(eq,Cs);

${_C6 = _C6}$

>	PDEtools:-Solve(eq,Cs);

Download maple_crash_Solve_oct_3_2025.mw

Also reported to Maplesoft support.

Physics:-Setup(assumingusesAssume = true): causes ...

Asked by: nm 11503

October 02 2025

0 2

I found very strange behaviour of Maple 2025.1 on Linux.

Same exact code. Calling timelimit(sol,ode) twice on two different solutions. If I do not add

Physics:-Setup(assumingusesAssume = true)

At the start, then both timelimits finish OK. But once Physics:-Setup(assumingusesAssume = true) is added at the start, the second timelimit hangs.

I waited 2 hrs and nothing happens. Maple just freezes. Can't even stop the server from worksheet by clicking on the red button at lower left corner.

This is using latest Physics. Does anyone know why this happens? It seems due to some memory cache issue?

Make sure to save all your work before trying this just in case you have to kill Maple application.

The strange thing, unable to stop the server by clicking on red button or clicking on RESTART KERNEL icon at top, or even clicking on the debuger icon at lower left corner. Only way was to kill Maple itself from Linux command line.

>	interface(version);

>	Physics:-Version();

>	SupportTools:-Version();

>

restart;

Example 1. Not using Physics:-Setup(assumingusesAssume = true): gives NO hang

>

sol_1:=y(x) = 1/2*(3*tan(RootOf(2*3^(1/2)*ln(2*3^(1/6)+(9*tan(_Z)*sec(_Z)^2+9*3^(1/2)*
sec(_Z)^2-8*3^(1/2))^(1/3))-3^(1/2)*ln(4*3^(1/3)-2*3^(1/6)*(9*tan(_Z)*sec(_Z)^2
+9*3^(1/2)*sec(_Z)^2-8*3^(1/2))^(1/3)+(9*tan(_Z)*sec(_Z)^2+9*3^(1/2)*sec(_Z)^2-\
8*3^(1/2))^(2/3))+12*_C2*3^(1/2)+12*3^(1/2)*x+36*I*_C2+36*I*x+6*_Z))^3*3^(1/2)+
9*tan(RootOf(2*3^(1/2)*ln(2*3^(1/6)+(9*tan(_Z)*sec(_Z)^2+9*3^(1/2)*sec(_Z)^2-8*
3^(1/2))^(1/3))-3^(1/2)*ln(4*3^(1/3)-2*3^(1/6)*(9*tan(_Z)*sec(_Z)^2+9*3^(1/2)*
sec(_Z)^2-8*3^(1/2))^(1/3)+(9*tan(_Z)*sec(_Z)^2+9*3^(1/2)*sec(_Z)^2-8*3^(1/2))^
(2/3))+12*_C2*3^(1/2)+12*3^(1/2)*x+36*I*_C2+36*I*x+6*_Z))^2+3*3^(1/2)*tan(
RootOf(2*3^(1/2)*ln((3*3^(1/2)*tan(_Z)*sec(_Z)^2-8+9*sec(_Z)^2)^(1/3)+2)-3^(1/2
)*ln((3*3^(1/2)*tan(_Z)*sec(_Z)^2-8+9*sec(_Z)^2)^(2/3)-2*(3*3^(1/2)*tan(_Z)*sec
(_Z)^2-8+9*sec(_Z)^2)^(1/3)+4)+36*I*_C2+36*I*x+12*_C2*3^(1/2)+12*3^(1/2)*x+6*_Z
))+1)^(1/3)*(I*3^(1/2)-1):
ode:=diff(y(x),x)-y(x)^3 = 8:
timelimit(30,odetest(sol_1,ode));

Error, (in simplify/ln/relations) time expired

>

sol_2:=y(x) = -1/2*(3*tan(RootOf(2*3^(1/2)*ln(2*3^(1/6)+(9*tan(_Z)*sec(_Z)^2+9*3^(1/2)
*sec(_Z)^2-8*3^(1/2))^(1/3))-3^(1/2)*ln(4*3^(1/3)-2*3^(1/6)*(9*tan(_Z)*sec(_Z)^
2+9*3^(1/2)*sec(_Z)^2-8*3^(1/2))^(1/3)+(9*tan(_Z)*sec(_Z)^2+9*3^(1/2)*sec(_Z)^2
-8*3^(1/2))^(2/3))+12*_C3*3^(1/2)+12*3^(1/2)*x-36*I*_C3-36*I*x+6*_Z))^3*3^(1/2)
+9*tan(RootOf(2*3^(1/2)*ln(2*3^(1/6)+(9*tan(_Z)*sec(_Z)^2+9*3^(1/2)*sec(_Z)^2-8
*3^(1/2))^(1/3))-3^(1/2)*ln(4*3^(1/3)-2*3^(1/6)*(9*tan(_Z)*sec(_Z)^2+9*3^(1/2)*
sec(_Z)^2-8*3^(1/2))^(1/3)+(9*tan(_Z)*sec(_Z)^2+9*3^(1/2)*sec(_Z)^2-8*3^(1/2))^
(2/3))+12*_C3*3^(1/2)+12*3^(1/2)*x-36*I*_C3-36*I*x+6*_Z))^2+3*3^(1/2)*tan(
RootOf(2*3^(1/2)*ln((3*3^(1/2)*tan(_Z)*sec(_Z)^2-8+9*sec(_Z)^2)^(1/3)+2)-3^(1/2
)*ln((3*3^(1/2)*tan(_Z)*sec(_Z)^2-8+9*sec(_Z)^2)^(2/3)-2*(3*3^(1/2)*tan(_Z)*sec
(_Z)^2-8+9*sec(_Z)^2)^(1/3)+4)-36*I*_C3-36*I*x+12*_C3*3^(1/2)+12*3^(1/2)*x+6*_Z
))+1)^(1/3)*(1+I*3^(1/2)):
timelimit(30,odetest(sol_2,ode));

Error, (in collect) time expired

>

Example 2. using Physics:-Setup(assumingusesAssume = true): second timelimit always hangs

>

restart;

>	Physics:-Setup(assumingusesAssume = true):

>

sol_1:=y(x) = 1/2*(3*tan(RootOf(2*3^(1/2)*ln(2*3^(1/6)+(9*tan(_Z)*sec(_Z)^2+9*3^(1/2)*
sec(_Z)^2-8*3^(1/2))^(1/3))-3^(1/2)*ln(4*3^(1/3)-2*3^(1/6)*(9*tan(_Z)*sec(_Z)^2
+9*3^(1/2)*sec(_Z)^2-8*3^(1/2))^(1/3)+(9*tan(_Z)*sec(_Z)^2+9*3^(1/2)*sec(_Z)^2-\
8*3^(1/2))^(2/3))+12*_C2*3^(1/2)+12*3^(1/2)*x+36*I*_C2+36*I*x+6*_Z))^3*3^(1/2)+
9*tan(RootOf(2*3^(1/2)*ln(2*3^(1/6)+(9*tan(_Z)*sec(_Z)^2+9*3^(1/2)*sec(_Z)^2-8*
3^(1/2))^(1/3))-3^(1/2)*ln(4*3^(1/3)-2*3^(1/6)*(9*tan(_Z)*sec(_Z)^2+9*3^(1/2)*
sec(_Z)^2-8*3^(1/2))^(1/3)+(9*tan(_Z)*sec(_Z)^2+9*3^(1/2)*sec(_Z)^2-8*3^(1/2))^
(2/3))+12*_C2*3^(1/2)+12*3^(1/2)*x+36*I*_C2+36*I*x+6*_Z))^2+3*3^(1/2)*tan(
RootOf(2*3^(1/2)*ln((3*3^(1/2)*tan(_Z)*sec(_Z)^2-8+9*sec(_Z)^2)^(1/3)+2)-3^(1/2
)*ln((3*3^(1/2)*tan(_Z)*sec(_Z)^2-8+9*sec(_Z)^2)^(2/3)-2*(3*3^(1/2)*tan(_Z)*sec
(_Z)^2-8+9*sec(_Z)^2)^(1/3)+4)+36*I*_C2+36*I*x+12*_C2*3^(1/2)+12*3^(1/2)*x+6*_Z
))+1)^(1/3)*(I*3^(1/2)-1):
ode:=diff(y(x),x)-y(x)^3 = 8:
timelimit(30,odetest(sol_1,ode));

Error, (in expand) time expired

>	#this below will now hang

>

sol_2:=y(x) = -1/2*(3*tan(RootOf(2*3^(1/2)*ln(2*3^(1/6)+(9*tan(_Z)*sec(_Z)^2+9*3^(1/2)
*sec(_Z)^2-8*3^(1/2))^(1/3))-3^(1/2)*ln(4*3^(1/3)-2*3^(1/6)*(9*tan(_Z)*sec(_Z)^
2+9*3^(1/2)*sec(_Z)^2-8*3^(1/2))^(1/3)+(9*tan(_Z)*sec(_Z)^2+9*3^(1/2)*sec(_Z)^2
-8*3^(1/2))^(2/3))+12*_C3*3^(1/2)+12*3^(1/2)*x-36*I*_C3-36*I*x+6*_Z))^3*3^(1/2)
+9*tan(RootOf(2*3^(1/2)*ln(2*3^(1/6)+(9*tan(_Z)*sec(_Z)^2+9*3^(1/2)*sec(_Z)^2-8
*3^(1/2))^(1/3))-3^(1/2)*ln(4*3^(1/3)-2*3^(1/6)*(9*tan(_Z)*sec(_Z)^2+9*3^(1/2)*
sec(_Z)^2-8*3^(1/2))^(1/3)+(9*tan(_Z)*sec(_Z)^2+9*3^(1/2)*sec(_Z)^2-8*3^(1/2))^
(2/3))+12*_C3*3^(1/2)+12*3^(1/2)*x-36*I*_C3-36*I*x+6*_Z))^2+3*3^(1/2)*tan(
RootOf(2*3^(1/2)*ln((3*3^(1/2)*tan(_Z)*sec(_Z)^2-8+9*sec(_Z)^2)^(1/3)+2)-3^(1/2
)*ln((3*3^(1/2)*tan(_Z)*sec(_Z)^2-8+9*sec(_Z)^2)^(2/3)-2*(3*3^(1/2)*tan(_Z)*sec
(_Z)^2-8+9*sec(_Z)^2)^(1/3)+4)-36*I*_C3-36*I*x+12*_C3*3^(1/2)+12*3^(1/2)*x+6*_Z
))+1)^(1/3)*(1+I*3^(1/2)):
timelimit(30,odetest(sol_2,ode));

Download hangs_timelimit_with_physics_maple_2025_1_oct_2_2025.mw

Could someone try to reproduce this on their Maple? If so, I will send bug report.

why dsolve gives Error, (in dsolve) this is a bug ...

Asked by: nm 11503

October 02 2025

1 0

Never seen such a message before

Here is MWE, Trace shows it comes from (SolveTools:-PolynomialSystemSolvers:-PseudoResultant:-AttemptFactorization,2)

>

restart;

>	interface(version);

>	Physics:-Version();

>	SupportTools:-Version();

>	ode:=diff(y(x),x$2)+3y(x)+D(y)(3)=0; IC:=y(1)+4y(2)+y(4)=0;

diff(diff(y(x), x), x)+3*y(x)+(D(y))(3) = 0

>	dsolve(ode)

x+(1/3)*3^(1/2)*(tan(3^(1/2)*x)-arctan(tan(3^(1/2)*x)))-((1/3)*(D(y(x)))(3)*(1+tan(3^(1/2)*x)^2)^(1/2)+(1+tan(3^(1/2)*x)^2)^(1/2)*y(x))*c__1-c__2 = 0

>	dsolve([ode,IC])

Error, (in dsolve) this is a bug

>

tracelast

dsolve called with arguments: [diff(diff(y(x), x), x)+3*y(x)+(D(y))(3) = 0, y(1)+4*y(2)+y(4) = 0], arbitraryconstants = subscripted, atomizenames = true, build = false, numeric = false, type = none
#(dsolve,80): error

\`dsolve/IC\` called with arguments: [diff(diff(y(x), x), x)+3*y(x)+(D(y))(3) = 0, y(1)+4*y(2)+y(4) = 0], {y(x)}, skipimplicit = false, skippparticularsolforlinearODEs = true, solution = {}, usesolutions = particular and general
#(\`dsolve/IC\`,53): return procname(_passed,':-usesolutions' = "general and particular")

\`dsolve/IC\` called with arguments: [diff(diff(y(x), x), x)+3*y(x)+(D(y))(3) = 0, y(1)+4*y(2)+y(4) = 0], {y(x)}, skipimplicit = false, skippparticularsolforlinearODEs = true, solution = {}, usesolutions = general and particular
#(\`dsolve/IC\`,57): ans := procname(_passed,':-usesolutions = "general"');

\`dsolve/IC\` called with arguments: [diff(diff(y(x), x), x)+3*y(x)+(D(y))(3) = 0, y(1)+4*y(2)+y(4) = 0], {y(x)}, skipimplicit = false, skippparticularsolforlinearODEs = true, solution = {}, usesolutions = general
#(\`dsolve/IC\`,277): zz := map(op,{\`dsolve/IC/_C\`({ANS[i]},funcs,x,ics)});

\`dsolve/IC/_C\` called with arguments: {y(x) = -(1/3)*(_C[1]*(D(_Z))(3)*(1+tan(3^(1/2)*x)^2)^(1/2)-3^(1/2)*tan(3^(1/2)*x)+3^(1/2)*arctan(tan(3^(1/2)*x))+3*_C[2]-3*x)/((1+tan(3^(1/2)*x)^2)^(1/2)*_C[1])}, {y(x)}, x, [y(1) = _C1, y(2) = _C2, y(4) = -_C1-4*_C2]
#(\`dsolve/IC/_C\`,1): ans := \`dsolve/IC/_C/do\`(solns,depvars,t,inits,'evaluated_ans', "default",':-giveup = giveup');

\`dsolve/IC/_C/do\` called with arguments: {y(x) = -(1/3)*(_C[1]*(D(_Z))(3)*(1+tan(3^(1/2)*x)^2)^(1/2)-3^(1/2)*tan(3^(1/2)*x)+3^(1/2)*arctan(tan(3^(1/2)*x))+3*_C[2]-3*x)/((1+tan(3^(1/2)*x)^2)^(1/2)*_C[1])}, {y(x)}, x, [y(1) = _C1, y(2) = _C2, y(4) = -_C1-4*_C2], evaluated_ans, default, giveup = giveup, usecansolve = false
#(\`dsolve/IC/_C/do\`,103): csol := [\`ODEtools/Solve/EnvDropMultiplicity\`(eqns,consts)];

\`ODEtools/Solve/EnvDropMultiplicity\` called with arguments: {-(1/3)*(_C[1]*(D(_Z))(3)*(1+tan(3^(1/2))^2)^(1/2)-3^(1/2)*tan(3^(1/2))+3^(1/2)*(3^(1/2)-Pi)+3*_C[2]-3)/((1+tan(3^(1/2))^2)^(1/2)*_C[1]) = _C1, -(1/3)*(_C[1]*(D(_Z))(3)*(1+tan(2*3^(1/2))^2)^(1/2)-3^(1/2)*tan(2*3^(1/2))+3^(1/2)*(2*3^(1/2)-Pi)+3*_C[2]-6)/((1+tan(2*3^(1/2))^2)^(1/2)*_C[1]) = _C2, -(1/3)*(_C[1]*(D(_Z))(3)*(1+tan(4*3^(1/2))^2)^(1/2)-3^(1/2)*tan(4*3^(1/2))+3^(1/2)*(4*3^(1/2)-2*Pi)+3*_C[2]-12)/((1+tan(4*3^(1/2))^2)^(1/2)*_C[1]) = -_C1-4*_C2}, {_C1, _C2, _C[1], _C[2]}, keepalreadysolveduntouched = false, removelabel = false
#(\`ODEtools/Solve/EnvDropMultiplicity\`,29): sol := :-solve(ee,X,_rest)

solve called with arguments: {-(1/3)*(_C[1]*(D(_Z))(3)*(1+tan(3^(1/2))^2)^(1/2)-3^(1/2)*tan(3^(1/2))+3^(1/2)*(3^(1/2)-Pi)+3*_C[2]-3)/((1+tan(3^(1/2))^2)^(1/2)*_C[1]) = _C1, -(1/3)*(_C[1]*(D(_Z))(3)*(1+tan(2*3^(1/2))^2)^(1/2)-3^(1/2)*tan(2*3^(1/2))+3^(1/2)*(2*3^(1/2)-Pi)+3*_C[2]-6)/((1+tan(2*3^(1/2))^2)^(1/2)*_C[1]) = _C2, -(1/3)*(_C[1]*(D(_Z))(3)*(1+tan(4*3^(1/2))^2)^(1/2)-3^(1/2)*tan(4*3^(1/2))+3^(1/2)*(4*3^(1/2)-2*Pi)+3*_C[2]-12)/((1+tan(4*3^(1/2))^2)^(1/2)*_C[1]) = -_C1-4*_C2}, {_C1, _C2, _C[1], _C[2]}, AllSolutions = FAIL, ConditionalSolutions = FAIL, DropMultiplicity = FAIL, Explicit = FAIL, MaxSols = FAIL, SolveOverReals = FAIL, SymbolicSolutions = true, TryHard = FAIL, UseAssumptions = false, domain = default, parameters = {}, parametric = false, split = false, useunits = FAIL
#(solve,133): _MaxSols := oldmaxsols

Engine:-Main called with arguments: {-(1/3)*(_C[1]*(D(_Z))(3)*(1+tan(3^(1/2))^2)^(1/2)-3^(1/2)*tan(3^(1/2))+3^(1/2)*(3^(1/2)-Pi)+3*_C[2]-3)/((1+tan(3^(1/2))^2)^(1/2)*_C[1]) = _C1, -(1/3)*(_C[1]*(D(_Z))(3)*(1+tan(2*3^(1/2))^2)^(1/2)-3^(1/2)*tan(2*3^(1/2))+3^(1/2)*(2*3^(1/2)-Pi)+3*_C[2]-6)/((1+tan(2*3^(1/2))^2)^(1/2)*_C[1]) = _C2, -(1/3)*(_C[1]*(D(_Z))(3)*(1+tan(4*3^(1/2))^2)^(1/2)-3^(1/2)*tan(4*3^(1/2))+3^(1/2)*(4*3^(1/2)-2*Pi)+3*_C[2]-12)/((1+tan(4*3^(1/2))^2)^(1/2)*_C[1]) = -_C1-4*_C2}, {}, {_C1, _C2, _C[1], _C[2]}
#(SolveTools:-Engine:-Main,37): sol := [SolveTools:-PolynomialSystem(eqns,vars,ineqs,':- maxsols' = \`if\`(type([_MaxSols],[{integer, infinity}]) and 0 < _MaxSols,_MaxSols,100))]

PolynomialSystem:-ModuleApply called with arguments: {-(1/3)*(_X000003*(D(_Z))(3)*(1+tan(3^(1/2))^2)^(1/2)-3^(1/2)*tan(3^(1/2))+3^(1/2)*(3^(1/2)-Pi)+3*_X000004-3)/((1+tan(3^(1/2))^2)^(1/2)*_X000003) = _X000001, -(1/3)*(_X000003*(D(_Z))(3)*(1+tan(2*3^(1/2))^2)^(1/2)-3^(1/2)*tan(2*3^(1/2))+3^(1/2)*(2*3^(1/2)-Pi)+3*_X000004-6)/((1+tan(2*3^(1/2))^2)^(1/2)*_X000003) = _X000002, -(1/3)*(_X000003*(D(_Z))(3)*(1+tan(4*3^(1/2))^2)^(1/2)-3^(1/2)*tan(4*3^(1/2))+3^(1/2)*(4*3^(1/2)-2*Pi)+3*_X000004-12)/((1+tan(4*3^(1/2))^2)^(1/2)*_X000003) = -_X000001-4*_X000002}, {_X000001, _X000002, _X000003, _X000004}, {}, FAIL, backsubstitute = true, domain = absolute, engine = default, explicit = false, maxsols = 100, preprocess = true, preservelabels = false, tryhard = true
#(SolveTools:-PolynomialSystem:-ModuleApply,15): sol := SolveTools:-PolynomialSystem:-Main(SolveTools:-Utilities:-New( equations,notz,SolveTools:-Utilities:-Intersect(vars,indets(equations ))),':-backsub' = reallybacksub,':-domain' = domain,':-maxsols' = realmaxsols,':-engine' = engine,':-preprocess' = preprocess,':- tryhard' = tryhard);

PolynomialSystem:-Main called with arguments: [{-(1/3)*(_X000003*(D(_Z))(3)*(1+tan(3^(1/2))^2)^(1/2)-3^(1/2)*tan(3^(1/2))+3^(1/2)*(3^(1/2)-Pi)+3*_X000004-3)/((1+tan(3^(1/2))^2)^(1/2)*_X000003)-_X000001, -(1/3)*(_X000003*(D(_Z))(3)*(1+tan(2*3^(1/2))^2)^(1/2)-3^(1/2)*tan(2*3^(1/2))+3^(1/2)*(2*3^(1/2)-Pi)+3*_X000004-6)/((1+tan(2*3^(1/2))^2)^(1/2)*_X000003)-_X000002, -(1/3)*(_X000003*(D(_Z))(3)*(1+tan(4*3^(1/2))^2)^(1/2)-3^(1/2)*tan(4*3^(1/2))+3^(1/2)*(4*3^(1/2)-2*Pi)+3*_X000004-12)/((1+tan(4*3^(1/2))^2)^(1/2)*_X000003)+_X000001+4*_X000002}, {3*(1+tan(3^(1/2))^2)^(1/2)*_X000003 <> 0, 3*(1+tan(2*3^(1/2))^2)^(1/2)*_X000003 <> 0, 3*(1+tan(4*3^(1/2))^2)^(1/2)*_X000003 <> 0}, {_X000001, _X000002, _X000003, _X000004}, {}, true, false, 1, {_X000001, _X000002, _X000003, _X000004}], backsub = true, domain = absolute, engine = default, maxsols = 100, preprocess = true, tryhard = true
#(SolveTools:-PolynomialSystem:-Main,86): sol := [SolveTools:-PolynomialSystemSolvers:- PseudoResultant(SolveTools:-Utilities:- GetEquations(sys),SolveTools:-Utilities:- GetVariables(sys),SolveTools:-Utilities:- GetInequations(sys),':-maxsols' = maxsols,':- tryhard' = tryhard)];

PseudoResultant:-ModuleApply called with arguments: {(_X000003*(D(_Z))(3)*(-2*cos(3^(1/2))+1+sec(3^(1/2)))+3*_X000001*_X000003*(-2*cos(3^(1/2))+sec(3^(1/2)))+3*_X000002*_X000003+3^(1/2)*tan(3^(1/2)))/cos(2*3^(1/2)), -(sec(4*3^(1/2))+sec(3^(1/2)))*_X000003*(D(_Z))(3)+3*(sec(4*3^(1/2))-sec(3^(1/2)))*_X000001*_X000003+12*_X000002*sec(4*3^(1/2))*_X000003+3^(1/2)*Pi+3^(1/2)*tan(4*3^(1/2))-3^(1/2)*tan(3^(1/2))}, {_X000001, _X000002, _X000003}, {_X000003 <> 0}, backsub = true, maxsols = 100, tryhard = true
#(SolveTools:-PolynomialSystemSolvers:-PseudoResultant:-ModuleApply,25): SolveTools:-PolynomialSystemSolvers:-PseudoResultant:-ApplySubstitution ({},[],numer(tm1),notzero union map(xx -> denom(xx) <> 0,tm1), unknowns);

ApplySubstitution called with arguments: {}, [], {_X000003*(D(_Z))(3)*sec(3^(1/2))+3*_X000001*sec(3^(1/2))*_X000003-2*_X000003*(D(_Z))(3)*cos(3^(1/2))-6*_X000001*_X000003*cos(3^(1/2))+3^(1/2)*tan(3^(1/2))+_X000003*(D(_Z))(3)+3*_X000002*_X000003, -_X000003*(D(_Z))(3)*sec(4*3^(1/2))+3*_X000001*sec(4*3^(1/2))*_X000003+12*_X000002*sec(4*3^(1/2))*_X000003+3^(1/2)*Pi+3^(1/2)*tan(4*3^(1/2))-_X000003*(D(_Z))(3)*sec(3^(1/2))-3*_X000001*sec(3^(1/2))*_X000003-3^(1/2)*tan(3^(1/2))}, {1 <> 0, _X000003 <> 0, cos(2*3^(1/2)) <> 0}, {_X000001, _X000002, _X000003}
#(SolveTools:-PolynomialSystemSolvers:-PseudoResultant:-ApplySubstitution,48): eqns := map(SolveTools:-PolynomialSystemSolvers:-PseudoResultant:- AttemptFactorization,eqns,not0,unknowns);

AttemptFactorization called with arguments: _X000003*(D(_Z))(3)*sec(3^(1/2))+3*_X000001*sec(3^(1/2))*_X000003-2*_X000003*(D(_Z))(3)*cos(3^(1/2))-6*_X000001*_X000003*cos(3^(1/2))+3^(1/2)*tan(3^(1/2))+_X000003*(D(_Z))(3)+3*_X000002*_X000003, {_X000003 <> 0, cos(2*3^(1/2)) <> 0}, {_X000001, _X000002, _X000003}
#(SolveTools:-PolynomialSystemSolvers:-PseudoResultant:-AttemptFactorization,2): error \`this is a bug\`

Error, (in dsolve) this is a bug

locals defined as: e = e

>

Download dsolve_error_this_is_bug_2025_1_oct_2_2025.mw

Note that changing the IC to IC:=y(1)+4*y(2)=0; makes it work with no error.

It is only when adding y(4) does the error shows up.

update Bug report emailed to Maplesoft.