I'm trying to use the CriticalPoints command from the Student[Calculus1] package to determine the critical points of f(x) = x^2 * ln(x).

My issue is this. A critical point is defined as a value of x in the domain of f(x) where either f'(x)=0 or f'(x) does not exist. Clearly x=0 is not in the domain of f(x) = x^2*ln(x). How may I "trick" Maple into returning only the value exp(-1/2)?  As seen above, my attempt to use the assuming command proved futile.

More troubling, however, is whether or not the CriticalPoints command is using the correct definition to compute critical points. Can anyone shed some light on this?

Download critpts.mw

Can someone explain to me, if you can, how the Euler angles on the plot interface work?

It looks like Phi is the rotation around z, Theta is the rotation around x, and Psi is around y. I'm trying to use matrices to compute the vector that is pointing towards your face as you're looking at the plot with the given Euler angles.

X := Matrix(3, 3, {(1, 1) = 1, (1, 2) = 0, (1, 3) = 0, (2, 1) = 0, (2, 2) = cos(phi), (2, 3) = sin(phi), (3, 1) = 0, (3, 2) = -sin(phi), (3, 3) = cos(phi)});

Y := Matrix(3, 3, {(1, 1) = cos(theta), (1, 2) = 0, (1, 3) = sin(theta), (2, 1) = 0, (2, 2) = 1, (2, 3) = 0, (3, 1) = -sin(theta), (3, 2) = 0, (3, 3) = cos(theta)});

Z := Matrix(3, 3, {(1, 1) = cos(psi), (1, 2) = sin(psi), (1, 3) = 0, (2, 1) = -sin(psi), (2, 2) = cos(psi), (2, 3) = 0, (3, 1) = 0, (3, 2) = 0, (3, 3) = 1});

and computing X*Y*Z*e3

TIA!

How do I define a function from a graph in a plot? 

Or how do I find the intersection between two lines? I have to find the intersection of 2 lines in a graph, while one of these lines consists of 2 different equations dependent from the same variable. 

Thanks in advance. 

I don't know how to write a function that determines whether a non-zero vector intersects a triangle with given vertices. If anybody could help me write a function that satisfies this so that the function returns true if the vector spanning the line intersects the triangle and returns false if it doesn't I would be greatly appreciative.

How to find the integral int(-2*log((1+sqrt(s))/(1-sqrt(s)))/((-s^2+1)*(s-1)*sqrt(s)), s = 0 .. z)

any general method to eliminate the derivative of lambda1,lambda2,lambda3

a:= -(diff(lambda1(t), t))+lambda3(t);
b:= -lambda1(t)-(diff(lambda2(t), t))+4*lambda3(t);
c:= -lambda2(t)+3*lambda3(t)-(diff(lambda3(t), t));

result in 2*lambda1(t) - lambda2(t) + 2*lambda3(t) = 0;

why are the results of gcd(x^2+1,x+1) mod 2 and Gcd(x^2+1,x+1) mod 2 in maple  different ? 

I know the  `mod`(gcd(x^2+1, x+1), 2);
                               1
`mod`(Gcd(x^2+1, x+1), 2);
                             x + 1

but how do you explains this question? give me reason?

solve({[(alpha[1]-alpha[2]*lambda)*sqrt(x)+p[2]*lambda]*[k[1]*(1-lambda^2)+2] = p[1]*(2*k[1]*(1-lambda^2)+2), [(alpha[2]-alpha[1]*lambda)*sqrt(x)+p[1]*lambda]*[k[2]*(1-lambda^2)+2] = p[2]*(2*k[2]*(1- lambda^2)+2)}, [p[1], p[2]])

Warning, solutions may have been lost

could you help me please to find a solution for this issue...

I would like to thank you in advance 

Best regards,

D.L.

I have to graph the following:

y=e^x, y=e^x+3, y=2*e^x, y=e^(x+3)

I put in plot(exp(x),exp(x)+3,exp(x)*2,exp(x+3)) but it is giving me Error, in plot (unexpected options): [exp(x)+3,exp(x)*2,exp(x+3)]

I can't figure out what I'm doing wrong!

It also will not allow me to graph ln(x)

Good afternoon sir.

I request you to provide the maple approach to workout Wielandt deflation & Hotelling deflation.

With thanks & Regards

M.Anand

Assistant Professor in Mathematics

SR International Institute of Technology,

Hyderabad, Andhra Pradesh, INDIA.

Hello dear friends

I have a difficult issue about the new maple 17, since I installed the new update i can't use my shortcut to Evalulate and Display Inline. Before i could use the Cmd + alt + =  or Cmd + = 

Now it just zooming in about 10% zoom size when i type this. I use this command alot, i hope you guys can help me with this.

I don't use worksheet, it's just maple math-mode 2d and I use macbook pro 10.6

Hi,

It should be simple, ...but results are wrong,
Please see for time above 4 hours.

What's wrong?

wzel

HT_one_layer_barrie.mw

Hello,

I try to calculate a big matrix product which is used after for the resolution of a differential system.

In the link below, you have the matrix product which causes me trouble.

http://dl.free.fr/p8fP9XqWn 

The matrix are composed with trigonometric functions.

I think that the problem is due to the fact that Maple tries to determine a analytical solution.

But, for my use, i only need a numerical result that i can use after for solving my differential system.

Have you some ideas in order to make this matrix product? 

Thank a lot

Dear All,

This's my first post on this website; I'm hoping I can get some useful ideas on how to approach the numerical solution for system of PDE's, with initial and boundary conditions.  I'm using Maple 15.

The PDE is,

pde:={diff(p(r,t),r)-v(r,t)^2/r-g1=0,diff(v(r,t),r$2)+beta*diff(diff(v(r,t),r$2),t)-diff(v(r,t),r)*(1/r)-(beta/r)*diff(diff(v(r,t),r),t) +diff(v(r,t),t)*(beta/r^2)+v(r,t)/r^2+(2/r + C*diff(p(r,t),r))*(diff(v(r,t),r)-v(r,t)/r+beta*diff(diff(v(r,t),r),t)- 1/r * beta*diff(v(r,t),t)-Re*(1+lambda)*exp(1-p(r,t))*diff(v(r,t),t)-(1+lambda)*exp(1-p(r,t))*g2=0};

The initial and boundary conditions are,

IBC:={p(1,t)=k,v(r,0)=0,v(1,t)=sint,v(2,t)=0}

I'm trying to solve and plot,

sol:=pdsolve(pde,IBC,numeric,time=t,range=0..1)

but i'm getting an error; (in pdsolve/numeric/match_pdes_bcs) cannot handle systems with multiple pde describing the time dependence of the same dependent variable or having no time dependence

Regards

J. Lee

f := Diff(u(t),t$2)+Diff(u(t),t)+u(t)+x(t);

after indicate to extract u(t), should output Diff(u(t),t$2)+Diff(u(t),t)+u(t)

after indicate to extract x(t), should output x(t)