Hi all,

I try many ways to solve the below DAEs, for example stiff=true, method = rkf45_dae, method=rosenbrock..., but my DAEs can't be solved. In different ways, there are different errors, such as "Warning, cannot evaluate the solution past the initial point, problem may be complex, initially singular or improperly set up", ""

Would you please show me how to solve the below DAEs and plot their solutions?

I really appreciate your help.

Hi!

I think I have quite simple problem, I can´t solve.

I have the following fraction:

and want to show it this way:

Multiplying the first fraction with (-1)/(-1) doesn´t work as expected.

Is there anyway to prevent Maple from converting a log10 function to a ln function when it displays a result?

Bonjour,

Qui peut m'éxpliquer l'algorithme de division d'un polynôme P(X,Y) sur un polynôme Q(x,y) ?

Avec mes plus vifs remmerciements,
Raymond Gérard.

after union ideal I and J, how to remove the intersection of I and J in order to do primedecomposition?

G1 := [v*y-w*x, r*y-u*x, -v*u+w*r, u*y^2-v*x^2, u^2*y-v*r*x, u*w*y-v^2*x, u^3-v*r^2, u^2*w-v^2*r, -v^3+u*w^2, x^4-r, x^3*y-u, x*y^3-v, y^4-w, w*y^2*x^2-v^2];

TypeTools[AddType](`w`,typefunc(string, symbol));
L:= `if`(G1::`w`, [op], '[]')(G1);

it seems above code incorrect.

Dear friends,

I wonder how I would go about calculating the asymptotic expansion of

sum(5^j/j, j=1..m+1)?

The motivation for this calculation can be found here. The correct answer is

5/4 5^(m+1)/(m+1).

The classic asympt and the one from multiseries both fail on this one.

Thanks,

Marko Riedel

i need your kind sggestions for this. i wrote the function w:=(xi(t),eta(t),diff(xi(t),t),diff(eta(t),t))→value.

but i cannot get the output, it wrote error in argument name. here value means the expression of the function.

best regards

Hi, I've got  a worksheet to do for my homework. I answered the first question, and then an error message appeared in the part of the code written by the teacher. At the following part,

Normalisation and expectation values of the superposition state
Lets consider the normalisation of, say, the mixed state Psi represented by the superposition of 1st and 2nd levels at an arbitrary time t.
int(evalc(conjugate(Psi(1,x,t))*Psi(1,x,t)),x=-infinity..infinity);

If Z is N(0,1) find

a) P(0<=Z<=.87)

I understand how to get to 0-0/1<=Z-0/1<=.87-0/1

which ends up being OI(.87), but am not sure how to get this to calculate. Plus I ant use proper functions here becuase I dont have the pallette, but OI is an O with the I through it... Φ(.87) I beleive....

I dont know how to have Maple calculate ths to give me the correct normal distribution value.

Hi all,

I have a differential equation as follows:

x(t)^2+cos(x(t))+diff(x(t), t)+diff(x(t), t, t) = 100

x(0)=2, D(x)(0) = 3;

After using "dsolve" to solve this equation, the solution x(t) is obtained.

How can we obtain the following function?

g(k) = ₀∫^kx²(t)dt

How can we plot the function g(k...

hi,

i have one equation (like equ1) wich this equatioin is a function of x. i want to find x in such a way that the equ1 minimizes. unfortunetly the equ1 is large and when i want to use NLPsolve it takes several time. is there any quick method to find the minimum x?

thanks for your attention in advance

How do I find the vertical asymptote of tan(x) when x=x/x+1?

I want to solve the equation 2*x-x*sqrt(x)-1)^(1/3)+sqrt(x)+(1-2*x)^(1/3) = 0 in real numbers. I tried

> restart:

with(RealDomain):

solve((2*x-x*sqrt(x)-1)^(1/3)+sqrt(x)+(1-2*x)^(1/3) = 0);

Maple out put loss the solution x = 0. I don't understand why.

Hi all,

First of all, I would like to mention that I'm new to Maple, so please excuse my lack of knowledge.

I have a rather complicated expression, let us call it expr, and I have a constraint equation, let us call it constr = 0. I would like to simplify expr knowing that constr = 0.

Stupid example:

expr: 2*x+4*y+3

constr: x+2*y = 0

In that case:

expr = 2*(x+2*y)+3 = 2*0+3 = 3

How can I do that?

Thanks a lot.