Dear all;

I need your help to get all the solution of this nonlinear  system  with four parameters: r1, r2, q1, q2  assumed to be positives. Let the system:

the first equation is: r1*x*(1-x/q1)=x*y/(1+x)

the second equation: r2*y*(exp(-y)-q2)=-x*y/(1+x)

How can get the positive solution ( x, y) of the previous system.

Thank you for your help.

Consider the function

The above definition may result in four cases depening on r and x.

Can Maple calculate automatically all possible cases and the corresponding Maxima, Minima and Values at intervals limits?

I have an ode in the form:

diff(u(x),x)-f(x)=u(x)^3+B(X)*u(x)+g(x)

how to extaract and name the different coefficients of the equation?

Thanks 

Hamada

Having a little trouble getting data from openstreetmap from export here

http://www.openstreetmap.org/export#map=17/43.4763/-80.5459

The system :

I am trying to recreate journal work for validating using another computer program so I am trying to use maple to solve the ODE, based on further research I found using laplace might be the best but I am having some trouble.

eq8:=d*(n(t)+C(t))/drho = -rho(t)/(l*alpha*K_c)

given the initial conditions of:

ICs:= n(0) = n_0, rho(0) = rho_0, C(0) = (beta-rho_0)*n_0/(l*lambda)

therefore: 

equation9 := dsolve({equation8, ICs}, {C(t), n(t)}, method = laplace)

Following this process I get the error: 

Error, (in dsolve) invalid initial condition

According to the journal work the solution I am looking for is: 

C(t)=-n(t)+(rho_0^2+rho(t)^2)/(2*l*alpha*K_c)+((Beta+l*lambda-rho_0)*n_0)/(l*lambda)

is there something that I'm doing wrong or missing? 

Any help would be greatly Appreciated! 

I want to simulate Inelastic collision

There has 2 ball which I can change  Quality and Radius.

one ball  move to another stirless ball with diferent angle

Hi

I need your help .. I solve a system and I get the error Warning, solutions may have been lost.

The maple code is attached.

testerror.mw

Thank you for your help.

hi everyone , i need your point of view in my question,any help would be appreciated in advance .

we have a discrete function named g(t) and a continous function f(t) in in convolution integral just like this :
int(f(t-x)*g(x),x=0..t) ; 
we have just g(x) in some special points int the interval (0..t) , thus i need to convert this integral to a series.
how should i do this ? can anyone help or any idea ? i need at first a mathematical solution or idea about how to do this and then, how to do this in a software ?
tnx again.

Dear all:

hello everybody;

I need your help to solve the system f(x,y)=0, and g(x,y)=0, such that there some parameter in the system, also all the parameter are positive and also our unkowns  x and y are also positive.

I try to write this code. I feel that under some condition we can have four solution or three or two. I need your help. Many thinks.

Systemsolve.mw

follow Computing non-commutative Groebner bases and Groebner bases for modules

using LeadingMonomials(f, lexdeg([s],[x,y]));

f:=[y^2+2*x^2*y, y^2];
f1:=[x+y^2,x];
f2:=[x,y];

g:=[f1,f2];

LeadingMonomial(g[1], lexdeg([s],[x,y]));
LeadingMonomial(g[2], lexdeg([s],[x,y]));
LeadingMonomial(g[1], lexdeg([s],[y,x]));
LeadingMonomial(g[2], lexdeg([s],[y,x]));

no result is (0,y^2)

where is wrong?

Determine the exact solution to the initial value problem

y'(x)=   (y(x)(20-y(x)))/80 , y(0)=1

 Compute a polynomial approximation to y(x). Plot this polynomial approximation together with y(x) on the same axes for x∈[0,20]. Choose different colours and linestyles for each curve.

Investigate whether or not it is possible to choose Order to be large enough to ensure that the plots of the polynomial approximation and y(x) are indistinguishable over the [0,20] interval? If this is possible, determine the minimum value of Order required. If you think that it is not possible, explain why not.

I tried

des := diff(y(x), x) = (1/80)*(y(x))(20-y(x))

and

ics := y(0) = 1

then i type

soln := dsolve({des, ics}, {y(x)})

came up with

y(x) = RootOf(x-(Int(80/_a(20-_a), _a = _b .. _Z))+80*(Int(1/_a(20-_a), _a = _b .. 1)))

then i tried 

Y := convert(rhs(soln), polynom)

it gives me the same thing

i put

PY := plot(y, x = 0 .. 20)

then it's error...

what should I do next?

I have a three paramter ode problem that involves three tanks with given initial concentrations.  Overtime the concentration equalizes but one of the steps is to determine all bifurcation values.  Not sure how to continue with this number of variables.

 This is our given system with initial conditions

sys_ode := diff(x(t),t) = (-r*x(t))/100+0+(r*z(t))/50, 
> diff(y(t),t) = (r*x(t))/100+(-r*y(t))/25+0,
> diff(z(t),t) = 0+(r*y(t))/25+(-r*z(t))/50;
> x0:=0; y0 := 200; z0:=0;

Hello,

I would like to copy/ paste my maplesim model in microsoft visio.

The idea is to create a vectorial illustration for presentation.

I manage to do this with simulink but not with Maplesim.

Apparently, when I go in visio, there is no possibility to copy like a metafile.

Is there a possibility to copy the object of a Maplesim model in a software like visio or illustrator so as to be able to create vectorial illustration for presentation ?

Thank you for your help.

I have two Reissner Nordstrom black holes that are near extreme. How do I show they move?