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I'm given the following two equations:

x^3-4x=y, y^3-4y=x

to solve the system, I've just used

eqns:={x^3-4x=y,y^3-4y=x};

vars:={x,y};

solns:=solve(eqns,vars);

and have obtained only four solutions when I should instead get 9. Is there a mistake in my approach?

Here's my problem,

I'm this line of code

result:=solve({x+y=1,x+2y=4},{x,y})
and the value of result is
{x=-2,y=3} and the value of result[1] is x=-2.

I would like the value of result to be {-2,3} for I need to use those output later. Is there any way to put those output in a list?

The following works as intended:

restart;
diff(x^7, x$i):
seq(%, i=0..7);

                              

Combining the two commands into one, however, does not work:

restart;
seq(diff(x^7, x$i), i=0..7);

          Error, invalid input: diff expects 2 or more arguments, but received 1

How does one explane this?  I was unable to find the reason by looking at the help page for seq().

I want to get a step-by-step solution of following integral:

Int(.5*exp(-s*t)*exp(-4.5*t)*sin(2*Pi*t), t)

how I can achieve this? Is there a Task for this? I tried Student Package but failed.

how to demonstrate the first quantization and second quantization of maxwell equation with physics package

How can this error be corrected '' error, (in fsolve) fsolve cannot solve on 0=0 ''. See the worksheet p4.mw

Thanks.

we always have subscript variable in the math book, but how could this be natral done in maple

I want to get a seq aaa3

seq(a[i],i=1..3)

but how could I get a  aij

seq(a[i_j],i=1..3);

and

seq(a[ij],i=1..3);  both was not right

Hello, I need a person who can help me with task from numerical methods.

I'm trying to solve some ODE analitically. But Maple gives me an incorrect solution. What am I doing wrong? Thank you.

 

Hello Guys,

i´m quite new to Maple and found a guide to draw an Ossannacircle with Maple.
The problem is, that it doesn´t work and i don´t get what´s wrong.

Could someone help?

 

That´s the code:

restart: with(plots):
interface(imaginaryunit=j, displayprecision=4):
plotsetup("inline",plotoutput=terminal,plotoptions="colour=cmyk,resolution=2000"):
U[n]:= 500: # V
U[2,n]:= 83.2: # V
I[1,n]:= 28.7: # A
phi[n]:= arccos(0.844):
evalf(180/Pi*phi[n]); # Grad
n[0]:= 1000: # 1/min
R1:= 0.465: R2:= 0.00985: # Ohm
ü:= U[n]/U[2,n]; # Übersetzungsverhältnis
I[1,0]:= 8.5: # A
phi[0]:= arccos(0.15):
evalf(180/Pi*phi[0]); # phi[0] in Grad
U[k]:= 170.5: # V
I[k]:= 28.7: # A
phi[k]:= arccos(0.277):
evalf(180/Pi*phi[k]); # phi[k] in Grad
I_[1,n]:= ?I[1,n]*exp(j*phi[n])?;
Pn_:= I_[1,n]:
I_[1,0]:= ?I[1,0]*exp(j*phi[0])?; P0_:= I_[1,0]:
I[1,k]:= ?I[1,n]*U[n]/U[k]?;
I_[1,k]:= 'I[1,k]*exp(j*phi[k])';
Pk_:= I_[1,k]:
G1:= '(Im(P0_)-xm)^2+(Re(P0_)-ym)^2 = r^2';
G2:= '(Im(Pk_)-xm)^2+(Re(Pk_)-ym)^2 = r^2';
G3:= '(Im(Pn_)-xm)^2+(Re(Pn_)-ym)^2 = r^2';
Loe:= solve({G1,G2,G3}, [xm,ym,r]);
assign(Loe);
linie:= proc(ap, ep, opt)
# ap... Anfangspunkt, ep...Endpunkt
# opt...Optionen (z.B. Farbe, Dicke); als Liste vorzugeben
plot([[Im(ap),Re(ap)],[Im(ep),Re(ep)]],op(opt));
end proc:
punkt:= proc(pp)
# pp... Zeiger auf den Punkt
pointplot([[Im(pp), Re(pp)]], symbol=solidcircle):
end proc:
kreis:= plottools[circle]([xm,ym], r, color=black):
P0:= punkt(P0_): Pk:= punkt(Pk_): Pn:= punkt(Pn_):
D_:= 'Re(P0_)+j*Im(Pk_)';
DD:= punkt(D_): # D ist für den Differentialoperator reserviert
P0D:= linie(P0_, D_, [color=black]):
DPk:= linie(D_, Pk_, [color=black]):
I_[2,k]:= 'I_[1,k]-I_[1,0]';
D_E:= 'Re(I_[2,k])*R[1]/(R[1]+R[2]*ü^2)';
E_:= 'D_ + D_E';
EE_:= 'E_ - P0_';
E:= punkt(E_):
ML:= linie(P0_, E_, [legend="Drehmomentlinie ", color=blue]):
LL:= linie(P0_, Pk_, [linestyle=dash, legend="Leistungslinie ",color=blue]):
I_10:= linie(0, P0_, [color=blue]):
d:= 0.05*Im(Pk_): # Textabstand
text:= textplot([[Im(P0_)-0.7*d, Re(P0_)+d/2,"P0"],[Im(Pn_)-0.7*d, Re(Pn_)+d/2,"Pn"], [Im(Pk_)+d, Re(Pk_),"Pk"],[Im(D_)+d/2, Re(D_)+1,"D"], [Im(E_)+d/2, Re(E_)+1,"E"]]):
KD:= display(kreis, P0, Pk, Pn, DD, E, I_10, LL, ML, P0D, DPk, text,scaling=constrained, title=typeset("Asynchronmotor\n U =",U[n], " V, I = ",I[1,n]," A\n"), titlefont=[TIMES,12,BOLD],labels=[typeset(Im('I[1]/A')),typeset(Re('I[1]/A'))]): KD;
G4:= ''(x-xm)*(xk-xm) + (y-ym)*(yk-ym) = r^2'';
G5:= isolate(G4,y);
G6:= collect(G5, x);
AA:= op(rhs(G6));
A := AA[1]/x;
G7:= isolate(A = Re(EE_)/Im(EE_), yk);
G8:= (xk-xm)^2 + (yk-ym)^2 = r^2;
Loe2:= solve({G7,G8}, [xk,yk]);
I_[1,kipp]:= subs(Loe2[1], j*xk + yk); Pkipp_:= I_[1,kipp]:
Pkipp:= punkt(Pkipp_):
LMS:= sqrt(3)*U[n]/1000; # Leistungsmaßstab in kW/A
DMS:= sqrt(3)*U[n]/(2*Pi*n[0]/60); # Drehmomentmaßstab in Nm/A
moment:= proc(P_)
local S; global P0_, E_, D_, DMS;
# Ermittlung der Strecke von P bis zur Drehmomentlinie
S:= Re(P_)-Re(P0_)-(Im(P_)-Im(P0_))*(Re(E_)-Re(D_))/
(Im(D_)- Im(P0_));
evalf(S*DMS);
end proc:
leistung:= proc(P_)
local S; global P0_, Pk_, D_, LMS;
# Ermittlung der Strecke von P bis zur Leistungslinie
S:= Re(P_)-Re(P0_)-(Im(P_)-Im(P0_))*(Re(Pk_)-Re(D_))/(Im(D_)-Im(P0_));
evalf(S*LMS);
end proc:
M[n]:= moment(Pn_);
Pmech[n]:= leistung(Pn_);
M[kipp]:= moment(Pkipp_);
Pmech[kipp]:= leistung(Pkipp_);
text2:= textplot([[Im(Pkipp_), Re(Pkipp_)+d, "Pkipp"]]):
plotsetup(ps, plotoutput="print", plotoptions="noborder,resolution=2000"):
display(KD, Pkipp, text2, labels=[" "," "], tickmarks=[0,0],caption=" ");
ZL:= readstat("Zeigerlänge vom Punkt (0,0) bis Pk in mm:");
IMSd:= abs(Pk_)/ZL; # A/mm
LMSd:= evalf(IMSd*U[n]*sqrt(3)/1000); # kW/mm
DMSd:= evalf(LMSd*1000/(2*Pi*n[0]/60)); # Nm/mm

 

Regards
Alex

I am currently running into an issue where the numerical solution to an equation (involving an integral, yes, but the value I am solving for is simly a constant in the integral) is taking significantly longer than I would hope it would to solve. I am solving a similar equation (with a simpler expression) and it is significantly easier to solve, and I am hoping for that kind of speed.

On the last two lines in the attachment, I have two expressions. The penultimate expression is the baseline speed that I would like to match. The last expression is the fsolve I would like to speed up.

Is there any way to numerically speed up the process? I found that when I did tracelast after halting the process, there were HUGE numbers being added and subtracted, multiplied and divided. Not only did this significantly slow down the proecss but it also adds much numerical instability, which I would also like to avoid.

All help would be appreciated.

pole-dragging-mapleprimes.mw

how to calculate the curvature of discrete data?

if discrete data have curvature, does it mean that it has quantum gravity?

but it may be some random data, it seems contradicts the fact

 

how to quantization of this curvature in maple?

 

I recently bought Maple 18 and noticed it was very unpleasant to look at. I saw it was running in low resolution on my Macbook Pro Retina late 2014. Why can I not untick it? This is not acceptable for the price I paid, and the fact I can't get my money back.

Any help would be highly appreciated.

how to compute non-reduced hilbert series?

hilbertseries return a simplified version of hilbert series,

 

how to output non-simplified version of hilbert series?

Hi there,

I've been trying to find an equivalent to MATLAB's unique command in Maple, but I had no success.

I've seen that Maple would return the elements that are either repeated (FindRepetitions) or not repeated (MakeUnique), but not the indices within the original list.

Is there way to do that?

Thanks,

jon

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