## Animating a phase portrait with parameter...

Hi there,

I've been asked to do the following and now I'm struggling to do part (c) (Part (a) and (b) are irrelevant!)

code for part(c): Qmaple.mw

So I want to animate the system of differential equations when a=1,and b as the parameter varying from 0.5 to 3,also 0<=x<=5,0<=y<=5;while t could be any arbitrary range from 0 to,say,50.However, I am not sure where to include b in my code.

## Copy from Maple 2016 to Ms Word...

Good day everyone,

I am having challenges copying equations from Maple 2016 to word. Anyone with useful information should share please.

Thank you in anticipation for your kind gesture

## evalf instead of solve in solving a system of diff...

Hi there,

I was asked to solve this problem:

and ending up with this:

Qmaple.mw

In Solut,if I replace evalf by solve I get a sensible solution.However,it is explicitly written in the question that I should use evalf to get an exact answer.How should I modify my code?

## Sinc(0) contradictory results...

The link below is to a worksheet giving the output of the sinc(0).  There is some contradictory results.  I know sinc(x)=sin(x)/x.  If x is very small then sinc(x)-->1.0 for either +-x.  However, for x = 0 is the function actually undefined or = 0 or = 1.0?  Check the link.  If you have an explanation I would like to be enlightened.

sinc(0).mw

## Plot a line of constant y in 3d?...

I am trying to plot what seems like a simple particle trajectory along the y-axis. How would I plot a function that is just moving in a constant line along the y-axis in 3d?

## Need to simplify the expression ...

Dear all!

Hope everyone is fine with everything! I want to simplify the following expression

diff(u(y, t), t) = (A^2/nu)^(1/3)*nu*(diff(u(y, t), y, y))/(A/nu^2)^(2/3)-(A^2/nu)^(1/3)*sigma*B^2*u(y, t)/rho+(A^2/nu)^(1/3)*g*beta*q2[w]*sqrt(nu^2/A)*T(y, t)/((nu*A)^(1/3)*k)+(A^2/nu)^(1/3)*g*beta*T[infinity]/(nu*A)^(1/3)-(A^2/nu)^(1/3)*g*beta*V[infinity]/(nu*A)^(1/3)+(A^2/nu)^(1/3)*g*beta1*C(y, t)/(nu*A)^(1/3)-(A^2/nu)^(1/3)*g*beta1*C[infinity]/(nu*A)^(1/3)

I above the red terms need to simplify i.e., we can add the power of A, nu etc. But maple can't do that please fix my problem. For more detail I attach my maple file.

simplify.mw

## Plotting an arbitrary Matrix ...

I am trying to plot matrix in maple, and from the help i believe i need to use matrix plot.

I am trying to do something like;

matrixplot(Matrix(2,2,{x^2,y^2,x*y,y},[x,y]);

for example. Is there a way to do this? Just like plotting a graph without specifying the range of x and y.

thanks

## Solve/fsolve won't work...

In the uploaded worksheet, using "solve" takes too long to evaluate and won't answer, while "fsolve" will only simply rewrite the equation. What am I missing?
1-parasitic.mw

## Problem to find integration...

Dearz!!!

Hope you all are fine. I am stuck to find the integration in the attachment. Please see that put your valuable suggestion to fix my problem. Thanks in advance

## Transform derivative into new set of variables...

Dear all!

Hope everything going fine. I want to transfrom the derivative diff(u, y) into diff(U, Y) as disscussed in attached file. Please see the attachment and fix the problem. Thanks in advance

Transform.mw

## How to find a specific point on a 3d plot...

This may be a very elementary question, but my searches on the topic have been unsuccessful, so I have to ask here. I've plotted a function using plot3d, and I want to find the exact value of the two variables for which the function equals a certain value. How can I find this point on the plot in the easiest way?
As an example, I have

And I want to find the points for which abs(zIT)-50=0. zIT is a function of L & C defined previously.

## Example using the product command...

How can i find the smallest n such that

using maple 2015?

I've tried using the solve command however this doesnt return a numerical value, any help would be great :)

## Regularize and evaluate an integral...

Is there a way in Maple to evaluate the following integral - where the "w" are set to go to zero to avoid singularities? B.t.w. Maple just returns the integral unevaluated with or without the "w" with the simple "int" command.

`int(ln(((p1-p3)^2+w^2)/(p1+p3)^(w^2+2))*ln(((p1-p4)^2+w^2)/((p1+p4)^2+w^2))*sin(p1)/(p1*p3*p4), p1 = 0 .. infinity);`

or even

`int(ln(((p1-p3)^2+w^2)/(p1+p3)^(w^2+2))*ln(((p1-p4)^2+w^2)/((p1+p4)^2+w^2))*sin(p1)/(p1*p3*p4), p1 = 0 .. 100, numeric);`

## Discrepancy on output of square root...

Not sure what is going on, but I confirmed the result is incorrect via MATLAB.  Can anyone tell me what MAPLE is doing?  Evaluation of the 1st expression is correct, but the 2nd expression = 0 is incorrect.  The correct answer should be 1.862645149230957e-08.

discrepancy.mw

## evalf/Sum and epsilon...

`(evalf@Sum)((1-10^(-3))^k/k, k = 1 .. infinity)`