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i have attcahed my ode with complex bvp

can anyone solved mine





Eq1 := (11-10*d)*(diff(h(eta), eta))+2*f(eta) = 0;

(11-10*d)*(diff(h(eta), eta))+2*f(eta) = 0


(11-10*d)*(diff(diff(f(eta), eta), eta))-h(eta)*(diff(f(eta), eta))-f(eta)^2+g(eta)^2 = 0


diff(diff(g(eta), eta), eta)-h(eta)*(diff(g(eta), eta))-2*f(eta)*g(eta) = 0


diff(p(eta), eta)+2*(diff(f(eta), eta))-2*f(eta)*h(eta) = 0




`Vλ` := [0.5e-1, 1.5, 1.5]:

etainf := 3:

bcs := h(0) = 0, p(0) = 0, (D(f))(0) = lambda*f(0)^(4/3)/(f(0)^2+(1-g(0))^2)^(1/3), (D(g))(0) = -Typesetting:-delayDotProduct(lambda*f(0)^(1/3)*(1-g(0)), 1/(f(0)^2+(1-g(0))^2)^(1/3)), f(etainf) = 0, g(etainf) = 0;

h(0) = 0, p(0) = 0, (D(f))(0) = lambda*f(0)^(4/3)/(f(0)^2+(1-g(0))^2)^(1/3), (D(g))(0) = -f(0)^(1/3)*(1-g(0))*lambda/(f(0)^2+(1-g(0))^2)^(1/3), f(3) = 0, g(3) = 0



dsys := {Eq1, Eq2, Eq3, Eq4, bcs}:

for i to 3 do lambda := `Vλ`[i]; dsol[i] := dsolve(dsys, numeric, continuation = d); print(lambda); print(dsol[i](0)) end do

Error, (in dsolve/numeric/bvp) singularity encountered







and attch back

Dear all,

I have a question: how to compute the roots of exp(z) = -1 with z in C? 

I tried: 

fsolve( exp(z) = -1, z, complex );

But it only gives one root (0.1671148658e-3+4.934802220*10^9*I) which does not even seem to be correct. I would prefere smth like z_n = I*(2*n-1)*pi or at least multiple roots...

By using

solve(exp(x) = -1, x);

it returns I*Pi.


MATLAB MuPAD gives the desired result:

solve(exp(x) = -1, x)

(PI*I + 2*PI*k*I, k in Z)




For my task I have to solve inequalities in the form

abs(z) < 1

With z being an expression yielding a complex number, but taking a real number as argument. Maple does not give any results when I pass such an expression to the function solve. It just immediately returns without any output.


What can I do to get the solution?


I have a complex equation EQ, it gives me 4 answers - two complex, one negative and one positive. Which assumptions do i need to use to automatically get one answer - real and positive one?

I tried similary to what I did with real equations:
simplify(solve(EQ)) assuming real, positive
But that didn't work

Is it possible to work with complex numbers in Maple T.A?

How could you for instance make a question where two complex numbers in polar form should be added. For instance (10<30deg)+(15<-10deg). I'm thinking of letting answers be in two fields, one for the absolute value and one for the angle but I would like to use random numbers in the two complex numbers to be added and would prefer to be able to use complex math in calculating the right answer.

So have to calculate frequency response of RLC-circuit
Long story short - I can't get how to solve something like this
solve(abs(I+x) = 1)
Obv - the answer is 0 or -I, but i get 1-I, -1-I instead

Hi experts,

attached the following code,, but i dont know what is the wrong with it, looking forward for helpful advise.

dsys :={diff(u(t),t)=-(N1+M*cos(2*I*omega*t))*u(t)-1+v(t)*exp(-2*I*omega*t)+w(t)*exp(2*I*omega*t), diff(v(t),t)=-(N1+I*Delta-2*M*exp(2*I*omega*t))*v(t)-(N1+u(t))*exp(2*I*omega*t)-2*M, diff(w(t),t)=-(N1-I*Delta-2*M*exp(-2*I*omega*t))*w(t)-(N1+u(t))*exp(-2*I*omega*t)-2*M}:
res:=dsolve(dsys union {u(0)=-1,v(0)=0,w(0)=0},numeric,output=listprocedure,maxfun=0):
plots[odeplot](res,[[t,(Re(w(t)))]],0..10,axes=boxed,titlefont=[SYMBOL,14],font=[1,1,18],color=black,linestyle=1,tickmarks=[3, 4],font=[1,1,14],thickness=2,titlefont=[SYMBOL,12]);
Warning, computation interrupted

how to plot ln(sqrt(x-12)/(-x^(2)+15x)

Whenever I try to plot I get 

"Warning, unable to evaluate the function to numeric values in the region; complex values were detected".


Hi there, 

I'm trying to find a way to find the Preimage for a single point (or a small set) of a complex rational function. I've tried with the command RationalMapPreimage, which sounds like the thing to try, but I can't get my head around how this command works?

(For context, I'm trying to find the preimages of a the fixed/critical/postcritial points of a function something like f(z)=(z2-1)/(z2+1))

Many Thanks

I have a vector, it is a zero vector apparently. I don't know what opperation lead to it being a zero vector. Any time I try to reduce this thing, I mess it up. I can't reduce it manually.







The simplify command will reduce this bugger no problem. The moment I try rationalizing the denominator or anything like that I end up buggering the whole thing up. Maybe I should do a distance on two of the ordinates independently first. Anyway, I don't know what's up. 

Hello everyone! I got some trouble in process a list. Hope you can help:

Assume i got a list like this:


{{k = k, l = RootOf(_Z^2+_Z*k+k^2-1), o = -k-RootOf(_Z^2+_Z*k+k^2-1)}, {k = k, l = RootOf(_Z^2+_Z*k+k^2+1), o = -k-RootOf(_Z^2+_Z*k+k^2+1)}, {k = 0, l = 1, o = -1}, {k = 0, l = -1, o = 1}, {k = 1, l = 0, o = -1}, {k = 1, l = -1, o = 0}, {k = -1, l = 0, o = 1}, {k = -1, l = 1, o = 0}, {k = RootOf(_Z^2+1), l = 0, o = -RootOf(_Z^2+1)}, {k = RootOf(_Z^2+1), l = -RootOf(_Z^2+1), o = 0}}


Now all i want is remove Complex and RootOf from this list, how can i do that?

Thank for your reading adn your help!



If I type this into a CAS calculator from Texas, I get the right result for Uc wich is 545.2.


This is used in AC circuits.

However, in Maple I'm using polar coordinates, so Im using this preamble:

phasor := proc (r, theta) options operator, arrow; r*cos(convert(theta*degrees, radians))+I*r*sin(convert(theta*degrees, radians)) end proc

This basically means that I can write phasor(value,angle in degrees) and get the lenth and angle of a vector on the complex plane.

Basically I want to know how I can make Maple solve this:

evalf(solve({phasor(U__C, -90) = phasor(400, X)-phasor(150, 0)+phasor(174.4, 90)}, {Uc, X})) Where I'm just interested in U_C , X doesn't matter.

I can't figure out how to do this with my current preamble. Does anyone know how to make this work?


I would like to know how to order a sequence of number from smallest to largest. This is if I have both real and imaginary numbers. Any help would be rgeatly appreciated! Thank you in advance.

Kind regards,

Gamiba Man

There are the complexes (C), quaternions (H or Q), octionions (O), sedenions (S) and the pathions (P). I have found the multiplication tables of them, although according to signs (+ or -) there differents at pathions. The important question is that How can I multiply two bases, i_n and i_m of higher dimensions, like in the routions or in the voudions?

Should I xor the indexes of the bases? Like this way: i_1 * i_2 = i_(1^2) = i_3

What is about the signs?

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