MaplePrimes Questions

Hi! I have the system of differential equations

restart; with(plots); with(DEtools);

a := 1;

deq1 := u(s)*(diff(varphi(s), s, s))+2*(diff(u(s), s))*(diff(varphi(s), s))+sin(varphi(s)) = 0;

deq2 := diff(u(s), s, s)-u(s)*(diff(varphi(s), s))^2-cos(varphi(s))+a*(u(s)-1) = 0;

sol := dsolve({deq1, deq2, u(0) = 1, varphi(0) = (1/4)*Pi, (D(u))(0) = 0, (D(varphi))(0) = 0}, {u(s), varphi(s)}, numeric)

 

which is perfectly solved, but I need to convert it to Cartesian coordinates and draw a plot, so what I tried is

x := u(s)*sin(varphi(s));

y := -u(s)*cos(varphi(s));

plot([x, y, s = 0 .. 20])

 

But I'm getting an error "Warning, expecting only range variable s in expressions [u(s)*sin(varphi(s)), -u(s)*cos(varphi(s))] to be plotted but found names [u, varphi]"

I don't know why is this happens if I have a solution. For example, I can get solution for 2 seconds:

sol(2)

[s = 2., u(s) = 2.33095721668252, diff(u(s), s) = 1.02513293353371, varphi(s) = .213677391510693, diff(varphi(s), s) = -.242430995691885]

 

I posted my question at here https://math.stackexchange.com/questions/2314488/how-can-i-find-maximum-and-minimum-modulus-of-a-complex-number.
With Mathematica, I got min is 22/5. This result is different from my solution by hand.

Repeat my problem. Let be the number z so that $|z+1| + 4|z-1| = 25$. Find the greastest and the least of the modulus of $z$. How can I find greastest and the least of modulus of z with Maple.

How can we find ricci tensor of a metric attaced in given file that involve two unknown functions phi(r) and nu(r).metric.mw

i have an optimization problem, i want to maximize an expression using assumption, what should i do?


 

restart:with(Optimization):

M1:=Matrix((1,4),[sqrt(p),0,0,sqrt(1-p)]);

M1 := Matrix(1, 4, {(1, 1) = p^(1/2), (1, 2) = 0, (1, 3) = 0, (1, 4) = (1-p)^(1/2)})

(1)

M2:=Matrix((1,4),[cos(theta[1])*cos(theta[2]),exp(I*phi[1])*sin(theta[1])*cos(theta[2]),exp(I*phi[2])*sin(theta[2])*cos(theta[1]),exp(I*(phi[1]+phi[2]))*sin(theta[1])*sin(theta[2])])^+;

M2 := Matrix(4, 1, {(1, 1) = cos(theta[1])*cos(theta[2]), (2, 1) = exp(I*phi[1])*sin(theta[1])*cos(theta[2]), (3, 1) = exp(I*phi[2])*sin(theta[2])*cos(theta[1]), (4, 1) = exp(I*(phi[1]+phi[2]))*sin(theta[1])*sin(theta[2])})

(2)

#Real:=rhs(op(op(2,Re(M1.M2))));

PP:=Re(M1.M2)(1,1);

Re(p^(1/2)*cos(theta[1])*cos(theta[2])+(1-p)^(1/2)*exp(I*(phi[1]+phi[2]))*sin(theta[1])*sin(theta[2]))

(3)

maximize(PP) assuming 0<p ,p<1;

Error, (in assuming) when calling 'maximize'. Received: 'invalid input: `minimize/continuous` expects its 2nd argument, yFP, to be of type {name, list(name)}, but received `theta[1]` = -infinity'

 

 


 

Download optimize.mw

I have final project to make a media for learning mathematic using maple. But I'm so confused to make a net of cuboid, anybody can help me? please :D

Why I receive this error:



 

Download Dchange.mw

It is evident that by repeated applications of the double-angle and product trigonometric identities, one may transform any monomial of the form sin(x)^p * cos(y)^q, where p and q are positive integers, to a linear combination of only first powers of sines and cosines.

Example 1:  The monomial  4*sin(x)*cos(y)^2 is equivalent to

 

Example 2: The monomial 16*sin(x)^2*cos(y)^3 is equivalent to             

How does one write a Maple procedure to do that transformation in the general case of sin(x)^p * cos(y)^q?

 

Dear All,

Please, could anyone point me out how to draw the beautiful Apollonian Gasket using Maple?

Thank you.

Very kind wishes,

Wang Zhe

Hello!

I crwated a polyhedron from by grouping vertices to faces, and faces to a shell. My goal is to convert the obtained object into a polyhedron, which behaves similarly as e.g. Archimedean solids generated by Maple. Is it possible? Thank you in advance!

Bests,

Andrzej

hello. how can i solve this integral. thank you

I am building an algebra 1 course for my school, and was wanting to create simple randomly generating practice sets for graphing points / lines / etc.

However, the Sketch answer type doesn't allow for any variable input like the other questions do. Is there a work around? 

Presuming a randomly generated $x and $y, is there any way to check to see if a student has plotted the point ($x, $y)?

I am student, and bought Maple student version 2017 and went through verification and activation with no probems and been using Maple for number of days.

But few days ago, I disconnected my internet service provider, and so now I have no access to the internet from my home PC where I installed Maple (I am writing this from  library)

Now at home, when I start Maple, I get a message saying that my licence will expire in 10 or 9  days or so. I do not understand this messge. Why it comes up now and did not come up before when I had internet access? 

Does one need to be connected to the internet all the time to use Maple? What if one does not have internet access?

I did remove one monitor from my PC also. Do you think Maple detected change in PC (one less monitor) and now it thinks this is new PC? But this makes no sense.

How do I tell Maple I have activated my Maple if I do not have internet access?

Hello Members,

I've to export some Maple lines to a LaTex file. I used the Maple command "Export as" and I saved the file like a .tex file. But when I open that file, it doesn't work because my LaTex doesn't recognise the package \usepackage{maplestd2e}.

How can I do? I put also my file in the post!

Thank you :)

hi, learners of maple like me, i was handling a project,but i came across this problem,and i began to doubt the accuracy of maple-plot,,,

very simply expression,result3,changing with the parameter f,

i first plot the f from 100 to 5000,

than i need to watch closer,

so i change the define domain of parameter f, plot f from 100 to 1000,  

and the result of plot definitely  differs from the previous one. 

low vally in the first figure (f in the scale of 100-1000),disappears! that's insane...

 

you can see below,

anyone see it, can you give me some clue? i really do not understand this. why ,why why,,

result3 := 3.269235506947450*10^11*sqrt(-1/(0.975698207102e-3*cos(0.19042716640833e-1*f)^2*cos(0.9521358320417e-2*f)^4-0.975698207102e-3*cos(0.19042716640833e-1*f)^2*cos(0.9521358320417e-2*f)^2+5.099915851388520*10^(-8)*cos(0.9521358320417e-2*f)^4-5.099915851388520*10^(-8)*cos(0.9521358320417e-2*f)^2+1.311634114532540*10^12*sin(0.19042716640833e-1*f)*sin(0.9521358320417e-2*f)*cos(0.9521358320417e-2*f)*cos(0.19042716640833e-1*f)+4.405792916762340*10^26*cos(0.19042716640833e-1*f)^2-4.406861706842330*10^26))

326923550694.745*(-1/(0.975698207102e-3*cos(0.19042716640833e-1*f)^2*cos(0.9521358320417e-2*f)^4-0.975698207102e-3*cos(0.19042716640833e-1*f)^2*cos(0.9521358320417e-2*f)^2+0.509991585138852e-7*cos(0.9521358320417e-2*f)^4-0.509991585138852e-7*cos(0.9521358320417e-2*f)^2+1311634114532.54*sin(0.19042716640833e-1*f)*sin(0.9521358320417e-2*f)*cos(0.9521358320417e-2*f)*cos(0.19042716640833e-1*f)+0.440579291676234e27*cos(0.19042716640833e-1*f)^2-0.440686170684233e27))^(1/2)

(1)

plot(result3, f = 100 .. 5000);

 

 

plot(result3, f = 100 .. 1000);

 

 

 

``


 

Download test.mw

 

 

 

doubt.mw

Equation21v2.mw

 

Hi,

When I do the derivation of a summation in order to one single term should not the result come out of the summation in the example attached in the file doubt? for example the derivative should not have yielded Ci and not the summation of Ci because for example if want the derivative in order to y1 it should be only C1 and not the summation of Ci.

 

The same happen when I go to a more complex case like in the file Equation21v2, should the result in the last double summation before T drop the summation over i to NC?

 

Many thanks in advance for your help!


 

5 6 7 8 9 10 11 Last Page 7 of 1467