## Find the candidates to absolute maximum and minimu...

Hello.

I am asked to find all the candidate points to absolute maximum or minimum in a domain delimited by several lines or curves.

Let me show you an example:

I am having trouble trying to find the candidate points on the boundary of the domain with LagrangeMultipliers.

How should I express the line or curve equations so that I can use them as constraints of LagrangeMultipliers? Should I use another method?

Thanks a lot.

## Why can't gfun guess the generating function of th...

That the Bernoulli numbers has z/(exp(z)-1)) as an exponentional generating functions is of course very well known. I am wondering why the gfun package doesn't seem to be able to work this out? Naive approaches like

gfun[guessgf]([seq(bernoulli(n),n=0..100)],z);

give FAIL. I would expect gfun to be able to transform the given sequence corresponding to replacing A(z) by 1/A(z), easily recognize (exp(z)-1))/z, and transform back. Perhaps the package is in need of maintenance?

Any help would be much appreciated.

Best,

Soren

## Solve maple function...

I want to solve a system of algebraic equations in maple using as follows:

equations:={b[1](2)*a[1](2, 1) = 1/2, b[1](2)*a[1](2, 1)^2 = 1/3, b[1](2)*a[2](2, 1) = 1/2, b[1](2)*a[2](2, 1)^2 = 1/3, b[2](2)*a[1](2, 1) = 1/2, b[2](2)*a[2](2, 1) = 1/2, b[1](2)*(a[3](2, 1)+a[3](2, 2))*a[1](2, 1) = 1/3, b[1](2)*(a[3](2, 1)+a[3](2, 2))*a[2](2, 1) = 1/3, b[1](2)*a[2](2, 1)*a[1](2, 1) = 1/3, b[1](1)*(a[3](1, 1)+a[3](1, 2))+b[1](2)*(a[3](2, 1)+a[3](2, 2)) = 1/2, b[1](1)*(a[3](1, 1)+a[3](1, 2))^2+b[1](2)*(a[3](2, 1)+a[3](2, 2))^2 = 1/3, b[2](1)*(a[3](1, 1)+a[3](1, 2))+b[2](2)*(a[3](2, 1)+a[3](2, 2)) = 1/2, b[1](1)+b[1](2) = 1, b[2](1)+b[2](2) = 1}

variables:={a[1](2, 1), a[2](2, 1), a[3](1, 1), a[3](1, 2), a[3](2, 1), a[3](2, 2), b[1](1), b[1](2), b[2](1), b[2](2), b[3](1), b[3](2)}

solve(equations,variables);

But I get an error mesage that the equations is not valid equation or expression.

Any help?

## How to collapse derivatives?...

Let

z := Diff(x(t),t)*y(t) + x(t)*Diff(y(t),t);

Is there a way to tell Maple to collapse that into Diff(x(t)*y(t), t) ?

I tried factor, combine, simplify, but none of them worked.

## Check if simplified...

Hi all,

I am looking for a boolean logic check to see if a rational expression is simplified.

For example: x/x^2  =  1/x  I want something along the lines of issimplified(x/x^2)=FALSE

Similarily, (x^2-x-12)/(x-4) = x+3  so I would like some logic test to say (x^2-x-12)/(x-4) is NOT simplified.

Mark

## How do I plot four second order curves in the same...

[[1000, 20], [2000, 25], [3000, 24], [4000, 23], [5000, 24]];
[[1000, 20], [2000, 25], [3000, 24], [4000, 23], [5000, 24]]
data1 := [[1000, 20], [2000, 21], [3000, 32], [4000, 23], [5000, 23]]; 'data1';
data1
a*x^3+b*x^2+c*x+d;
3      2
a x  + b x  + c x + d
x;
x
Equn1 := CurveFitting[LeastSquares]([[1000, 20], [2000, 25], [3000, 24], [4000, 23], [5000, 24]], x, curve = a*x^3+b*x^2+c*x+d);
plot(Equn1,x= 1000..5000)

Least Squares Approximation

Calculate a least squares approximation using specified data points.

Theoretical Curves for the Two-Stroke Engines and Four-Stroke Engines Brake Power Vs Brake Efficiency

List of Data Points:

 >
 (1)
 >
 (2)

Fitting Curve:

 >
 (3)

Independent Variable:

 >
 (4)

Least Squares Curve:

 >
 > plot(Equn1,x= 1000..5000)
 >

 >
 (5)

Least Squares Fit of Data by a Specified Curve

List of Data Points:

 >
 (6)

Fitting Curve:

 >
 (7)

Independent Variable:

 >
 (8)

Least Squares Curve:

 >
 (9)

 (10)

The above command plots one curve alright. I want four such curves to go in the same figure using command like

plot(Equn1,Equn2,Equn3,Equn4,view(x=1000..5000)

I am not getting by the above command what I want. Can any one help. A shortcut method is required for me to repeat many times.

Thanks for help.

Ramakrishnav V

## Arithmetic operations on finite field...

Hello!, Is there any package to do arithmetic operations on finite field?

Example: Z(5) - over field 5: calculate with remainders:

(x^8 + 2x^4 + 1) / (x^5 + 4x^3 + x^2 + 3x +3).

thanks.

## Special operators in Maple...

Below I wanted Maple to calculate the 4. degree Taylorpolynomium of a function f around x = 7. As shown below, Maple delivers a polynomial, but not a function definition. In other words one cannot have the polynomial evaluated at a specific value. The reason for this is obvious: The value 3 of x is passed to the command, implying 3 = 7 is a parameter to the command: Therefore the error message. I solved the problem by using the unapply command, but this operation is a bit tedious. I think I remember there is another more simple operator to make the same happen in Maple. I hope someone can remind me of that one!

Regards,

Erik

## computation geometry...

Hi

Is there any idea using Maple  to compute the leg lengths  in Stewart-Gough platform ( see the following figure)

I would like to make a code using cross-product and the unit Normal N

·       P is of length 13 and displaced in the Y direction by 10 degrees from the vertical (Z axis)

·       N is displaced in the X direction by 18 degrees from the vertical (Z axis)

·       LB is position [7 5] from the bottom plate centre in the XY plane

·       LT is in position [3.5 4.2] from the top-plate centre in the AB plane

Many thanks for any help

## Integral of complex function ...

I need to calculate the following complex integral:

oint_C { [(z^4exp(2z)+1)/(z+i)^3] - [(z^3+z)/{(z-2i)(z-5)}] + 8*Pi*exp } dz,

Where C is the circumference |z-1| = sqrt(11/2), positively oriented.

Someone can help me, I already researched but I can not integrate.

## Matrix which have matrix entry...

I know that is easy for you but i am new in this topics.I want to write a code to generate a matrix which have entries consist of matrices(it has differnt dimensions)

## A simple limit - bug...

L := sum( 1/ln(k), k=2..n ) * ln(n)/n;

limit(L, n=infinity);
0
# Should be 1

Just curious: in Maple 2017, is it OK?

## What kind of data could i get from the new world m...

First at all, congratulation for the new update Maple 2017!!.                                        I'm a personal developer about renewable energy hybrid systems models. It is possible get data about irradiance or wind speed from the new world maps?. It will be very interesting!!!                                                                                   Thanks!!!!

## How do I solve this problem in MapleSim?...

Hi, i don't know what happened but every time that I run the simulation appears this:

 invalid input: Multibody:-GetMultibodyData expects its 4th argument, lsProbes, to be of type list(list), but received registerMultibodyVariable If anyone can solve this problem, I am going to be very grateful. Thanks Main