Let F(x, y) = 4x + 5ye i + 5y cos y + 5xe j.

> P := (x, y)− > 4 ∗ x^2 + 5 ∗ y ∗ exp(x ∗ y);

> Q := (x, y)− > 5 ∗ y ∗ cos(y) + 5 ∗ x ∗ exp(x ∗ y);

> diff(Q(x, y), x) − diff(P(x, y), y);



Is the vector field F conservative? (YES or NO)

 

Hi everyone!

  I have something I would like maple to compute for me, but I am not sure how to enter it.  Here is the situation:

 

I have 4 equations with 5 unknowns.  I would like maple to solve for 4 of the unknowns.  Eventually I need 1 unknown in terms of just one other unknown.  An example would be

 

0=a₀+a₁+2a₂                     eq(1)

Specifically, the summation, product and limit expressions aren't displaying their indicies/limits correctly. Instead of sitting on to and directly below the symbol, they are mashed in the center. No idea why.

Maple gave the following answer

x=RootOf( _Z^2*a+1, label=_L1)*b

Does it mean that

(x/b)^2*a+1=0 ?

Thanks.

 

I tried to use the Statistics package to compute an expected utility, which is the mean of the product of a utility function u and a random variable f.

E.g. I have a random variable, which is binomial distributed and a utility function: u:=t->-exp(-a*t);

How do I tell Maple to compute the Mean of that product of a random variable and a utility function (i.e. to compute the expected utility)?

Anyhow, if someone knows a more efficient way, I´d also be glad to hear your suggestions.

Thanks for helping.

 

 

I tried solving a system of PDEs in composite domain (see the attached image below), but couldn't get pdsolve to work for some reason. The error I got is: "Error, (in pdsolve/numeric) initial/boundary conditions must be defined at one or two points for each independent variable."

Would someone please let me know what I did wrong?

Hi

I want to simplify sin(x)/cos(x) to tan(x).

i have tried command simplify(sin(x)/cos(x),trig);

and

trigsubs(tan(x))[4] = sin(x)/cos(x)

(wrong way round)

rgds

I tried the following:

u1:=t->-exp(-a*t);
h1:=t->piecewise(t < 0, 0, binomial(n, t)*p^t*(1-p)^(n-t));
k1:=t->piecewise(type(h1(t), And(realcons,Not(infinity) ) ), h1(t), 0);
 

add(k1(t)*u1(t),t=-infinity..infinity);  [didn´t work. maybe 'add' kann only compute a finite number.]

First question: => How am I going to compute an EV, i.e. the sum from -infinity to infinity?

 

Next I tried:

Hey guys i am currently attempting to do some modelling with maple, i need to solve a PDE system, i am using the following code and am confused with the error i'm getting. restart: M[Star]:=2*10^30: M[planet]:=2*10^27: q:=(M[planet])/(M[Star]): g:=sqrt((R-a)^(2)): H:=0.0333*R^(1): Delta[p]:=H: Alpha := unapply(piecewise(R <> a, 6.67*q^2*10^(-11)*M[Star]*(a/Delta[p])^4/(2*R), R = a, 1), R, a)

Hi.

I defined the following functions:

 

Hi there,

 

I'm using Maple 13.02 on Windows 7 64-bit.

I get the error message Error, (in plot) type `has_unit` does not exist every time I try to make a plot.

Example:

plot(x^2,x=-1..1) gives this error.

 

Dou you know what's wrong?

 

Have a nice day!

H.C., Denmark.

With the help of maple, how could I solve this one? Determine all values of c guaranteed by the Mean Value Theorem for
f (x) = 2 x^5 + x4^ - 3 x^3 + x^2 - x - 1 on [ - 1, 1].

Hello,

I have about 30 equations, let's call them S_i

I want to plot them. Each S_i is defined for some x between x_i and x_i+1

In other words, i want to plot:

S₀  for x₀ < x < x₁

S₁  for x₁ < x < x₂

S₂  for x₂ < x < x₃

S₃  for x₃ < x < x₄

... all the way to i=29

Hello,

I've performed the exact same calculation (using the exact same worksheet, with absolutely no changes made) last night and today and got these results:

y=[0, .4646313991, .9499094532, .5799050874, .1092604065, .4031507404, .8483735670, .6138799333, .1913933456, .3724618402, .7707837830];

y=[0, .4646313991, .9499094532, .5799050874, .1092604061, .4031507404, .8483735643, .6138799354, .1913933461, .3724618343, .7707837938];

 

Which are exactly the same modulo the last 3 digits.

Digits=10 in both cases.

I'm solving a differential equation in a region of appearing and disappearing potential energy, hence there is a piecewise function in the PDE w.r.t. time. The potential disappears randomly, and I need to generate a set of random times about a mean that I can put into the piecewise function to achieve this. What is the best way of generating random numbers modelled by a Poisson distribution so they can be fed into a function? Any help appreciated, Ryan