Hello Guys,

Can maple derive Einstein field equations from Einstein-Hilbert action ?

Thx

hello guys, I can't take the real part of this formula that you can see in the picture that I upload for you.
please help me!!!!!!!!
sorry for uploading photo...so surry

I want to see that if parameter 'alpha' tends to the infinity amount of parameter 'p' how changes?

how I can see and do  this process?

thanks

_nahaii.mw
 

Download _nahaii.mw

Hi every body:

I want to solve these equations with maple, can everyone help me how to solve them?

eq1 := diff(u1(x), x, x)+diff(u2(x), x)+int(2*x*s*(u1(s)-3*u2(s)), s = 0 .. 1) = 6*x^2+3*x*(1/10)+8
eq2 := diff(u1(x), x)+diff(u2(x), x, x)+int((3*(s^2+2*x))*(u1(s)-2*u2(s)), s = 0 .. 1) = 21*x+4/5
bcs := u1(0)+(D(u1))(0) = 1, u2(0)+(D(u2))(0) = 1, u1(1)+(D(u1))(1) = 10, u2(1)+(D(u2))(1) = 7

with regards...

I want to plot these in one frame:

between [0, 0.2]

between [0.2, 0.4]

betwen [0.4,0.6]

between [0.6, 0.8]

I want to plot all these functions y[0], y[1], y[2], y[3] in one plot between the mentioned interval.

Below is an attempt to evaluate an integral from t to ZERO.  I believe the issue is that sin(x) in the denominator is causing a problem.  However, in actuality sin(nx) is in the numerator so at the lower integral bound approaching ZERO the factor of n remains.  So how can I get MAPLE to evaluate this correctly?
 

Download evaluating_integral.mw

Hello,

I'm trying to evaluate an integral (code snippet and screen-shot included below) assuming that certain parameters and integers. Using assume statements the integral evaluates to 0. However, if I evaluate the integral for a specific set of integers, the integral evaluates as non-zero.

Can anyone clarify why the two int statements return different values?

Thanks!

assume(K::integer);
assume(L::integer);
assume(M::integer);
int(sin(K*x)*sin(L*x)*cos(M*x), x = 0 .. Pi);
     returns: 0
int(sin(14*x)*sin(2*x)*cos(12*x), x = 0 .. Pi);
     returns: Pi/4

I have the following maple code. 

R11 := x -> (x+2*a_1)*(product(x+b[j], j = 1 .. k-n))/(x+a_1);

T_4 :=  (z_1, z_2, z_3, z_4) -> R11(z_1)*z_2*z_3*z_4;

%*(z_1+a_1);

I would like maple to simplify (z_1+a_1) in the denominator of R11(z_1) with the (z_1+a_1) from the last line, but it does not do that. Simplify command also does not help.

On the example of a manipulator with three degrees of freedom.
A mathematical model is created that takes into account degrees of freedom of the manipulator and the trajectory of the movement from the initial point to the final one (in the figure, the ends of the red curve). In the text of the program, these are the equations fi, i = 1..5.
Obviously, the straight line could be the simplest trajectory, but we will consider a slightly different variant. The solution of the system of equations is the coordinates of the points of the manipulator (x1, x2, x3) and (x4, x5, x6) in all trajectory. After that, knowing the lengths of the links and the coordinates of the points at each moment of time, any angles of the manipulator are calculated. The same selected trajectory is reproduced from these angles. The possible angles are displayed by black color.
All the work on creating a mathematical model and calculating the angles can be done without the manipulator itself, is sufficient to have only the instruction with technical characteristics.
To display some angles, the procedure created by vv is used.
MAN_2.mw

I am trying to learn how to use the Physics tensor routines by using a simple 2D example.  In the following, I set up the Cartesian Euclidean metric tensor and then tried to transform to cylindrical coordinates.  The metric tensor is correctly transformed in line (5), but then when it is called in line (7), it still has Cartesian values.  What am I doing wrong?

with(LinearAlgebra);
DotProduct([a, b], [c, d]);

gives

Does it think that I want my variables complex conjugated? (And why?) How do i turn it off?

Hello.
I can not find a tool for calculating the number of permutations with fixed points. I looked at the package combinat. Help me please.

Hello,

I have a question: Hw can I add a straight line in the following plot?

2018-01-20_Biegeversuch_Ablauf.mw

Thank you very much!

Martin

Dear sir,

 i want to plot a graph with  tick marks on all sides , i am attaching codes and  a sample graph, see the attachmnent,

The graph range should be displace only on x and y axis and the vaues should not be on opposite to x and y axis

please see the sample graph

restart:
h:=z->1-(delta2/2)*(1 + cos(2*(Pi/L1)*(z - d1 - L1))):
K1:=((4/h(z)^4)-(sin(alpha)/F)-h(z)^2+Nb*h(z)^4):
lambda:=Int(K1,z=0..1):
F:=0.3:
L1:=0.2:
d1:=0.2:
alpha:=Pi/6:
plot( [seq(eval(lambda, Nb=j), j in [0.1,0.2,0.3])], delta2=0.02..0.1);

hi everyone
 

I am trying to call the maple function fsolve in the matlab. I have used maple('fsolve(x^2-4)'). It worked.Now in the matlab code I have defined another variable. let us say a = 10.  Now I am trying to call the fsolve as follows.

a=10;

maple('fsolve(a*x^2-1)')

I ended up with the following error :

Error, (in fsolve) number of equations, 1, does not match number of variables, 

could any body help? tnx