MaplePrimes - Questions and Posts tagged with equation

mod equation over integers

mantas84 — Sun, 12 May 2013 19:01:39 Z

hello,

I need to find a sollution for equation in maple 14

a*s = b mod c, where a, b, c are know integers, for example

Why does maple display my solution in terms of variables instead of solving my maximalization equation?

FKil — Sat, 11 May 2013 08:59:55 Z

Dear members,

I am trying to solve a maximalization problem, but in stead of solving my problem Maple only displays the equation that I am trying to solve.

Example:

> Sigma_max:= maximize(-N/(b*h)+(-EI*(diff(u(x),x,x)))*0.5*h/I, x=0..l = sigma_t;

sigma_max:=maximize(-0.400000cos(0.25pi)N+564e*N*x .....etc...., x = 0..250)=1.43 10⁶

Explicit equation of arbitrary continuous piecewise linear function

Kitonum — Tue, 30 Apr 2013 16:16:55 Z

It's interesting that every continuous piecewise linear function can be specified by one explicit equation with absolute values. The procedure JoggedLine carries out such conversion.

Formal arguments of the procedure:

A - a list of the coordinates of the vertices of the polyline or the continuous piecewise linear expression defined on the entire real axis.

B (optional) - a point on the left "tail"...

transcendental equation plot on complex plane

maple fan — Fri, 26 Apr 2013 06:07:38 Z

hello,everyone,
I have a problem to make a figure, commands are below:

restart;
1+(2*(S1*e2/(S2*e1)+S2*e1/(S1*e2)))*tanh(S2*k*d);
S1 = sqrt(beta^2-e1), S2 = sqrt(beta^2-e2);
e1 = 4, e2 = -19-.53*I;
subs(`%%`, %, k = 2*Pi/(0.633e-6), `%%%`);

I want to plot the relation between d and beta(real part named betar and imaginary part betai),but meet some trouble.
I got some points from the article is when d=400e-10, betar in the range (2.1,2.2...

How do i solve an equation with 2 variables (x,y) for a specific list of values for y ?

Hak — Thu, 04 Apr 2013 18:57:47 Z

Hello,

First of all I just want to say that your forum is great and it helped me to find a lot of new stuff for Maple. I am yet still a beginner but …we all need to learn. So let’s get to my question. I have an equation with 2 variables - x and y. This is the equation

x = y*(25+2*x)^(2/3)/(25*(.566*(25*x)^(2/3)))

So… I know I can solve the equation for x and y and I can give it specific values for y and it solve it every time. When,...

Vector solve.. HELP!

runebrasmussen — Sat, 30 Mar 2013 10:19:36 Z

Hi.

I want to solve two varibles from a vector crossproduct equation, but receives a failure massage no matter what i do.
The equation is the one below and i want to solve for Gx and Gy.

Really hope you can help.. THANKS!

with(LinearAlgebra);
F1:=<Fr1,-Ft1,-Fa1>;
Sug :=<0,0,-Duzg>;
Su1:=<Dux1,0,-Duz1>;
Mmotor:=<0,0,-Mind>;
G:=<Gx,Gy,Gz>;
OO:=<0,0,0>;
        
U:=(Su1 &x F1) + (Sug &x G) - Mmotor = OO;...

How to split or directly plot a system of solved differential equations

OffshoreEngineer — Tue, 19 Mar 2013 13:43:48 Z

Hi all,

I am new to Maple and I have (possibly a simple) question. I'm solving 2 coupled differential equation, it all goes well, until I want to plot them.

I have the output in the following form:

sol = {w1(x) = [ -a*x^4+b*x^3-c*x]}, {w2(x) = [-d*x^4+e*x^3-f*x^2+gx-h]}

My goal is now to plot the solution in 1 figure with w1(x) between x=0..100000 and w2(x) between x=100000..150000

I have searched on the web for a way to get the formula's of w1(x...

find max of values, save solve values

reemeaaaah — Mon, 18 Mar 2013 05:05:40 Z

Hello

I am trying to find the maximum of values in dsolve. In part 1 we solve the equation. In part 2 we do a doolop to know the values for specific time such as t=2. In part 3 we try to give this values names such as y[i] then to find the maximum of these values but it did not work for the maximum it gave y6 instead of the value.

Also, is it possible to save all values from dsolve to a file the call it to find the maximum at each t?

Assign name to one of multiple results

9colai — Thu, 14 Mar 2013 13:22:27 Z

Hi!

I need to assign a name to a result calculated from a system of equations. In this case, i've got 2 equations and 2 solutions. I want to assign a name to the each of the solutions.

solve({-a+4*b = 0, 2*a+7*b = 2}, {a, b})

{a = 8/15, b = 2/15}

How do i assign a name for a and another for b?

rearring equations

gdog — Wed, 06 Mar 2013 10:28:10 Z

Hi I know this is a simple question but i have completely forgotten how to do it: I have the following equation,

h := ((A-B)^2*(A-4-B^2+4*B)*(A-4-B^2-4*B)-Q^2*(A-4-B^2+4*B))/(Q^2*(A-4-B^2-4*B))-1

how can I find what B is equal to?

boundary conditions are not been utilized need help

emma hassan — Mon, 04 Mar 2013 23:45:49 Z

hello friends am working on 2d heat equation and i have writen maple code for it but its not running because my scheme is having fictitious points which are removed by using boundary conditions but in this code which i have written the line in bold is not using boundary conditions due to which my fictitious points are still in programe and its not working am attaching my worksheet

trytimg.mw

please let me know where am wrong thank you...

integral of solution of differential equation

STHence — Sat, 02 Mar 2013 09:01:57 Z

Hi all,

I have a differential equation as follows:

x(t)^2+cos(x(t))+diff(x(t), t)+diff(x(t), t, t) = 100

x(0)=2, D(x)(0) = 3;

After using "dsolve" to solve this equation, the solution x(t) is obtained.

How can we obtain the following function?

g(k) = ₀∫^kx²(t)dt

How can we plot the function g(k...

Plug a constraint into an equation

PlpPlp — Fri, 01 Mar 2013 13:02:42 Z

Hi all,

First of all, I would like to mention that I'm new to Maple, so please excuse my lack of knowledge.

I have a rather complicated expression, let us call it expr, and I have a constraint equation, let us call it constr = 0. I would like to simplify expr knowing that constr = 0.

Stupid example:

expr: 2*x+4*y+3

constr: x+2*y = 0

In that case:

expr = 2*(x+2*y)+3 = 2*0+3 = 3

How can I do that?

Thanks a lot.

Set of expressions to matrix

sebastianus — Sun, 24 Feb 2013 16:05:38 Z

How can I use factor in equations?

saeidansari — Thu, 14 Feb 2013 07:21:29 Z

How can I use factor in equations?

For example:

x^6+y*x^4+z*x^2-g*x^4-3*x^6====>-2*x^6+(y-g)*x^4+z*x^2

a*cn+w*dn+e*cn+f*dn=====>(a+e)*cn+(w+f)*dn

These examples are very simple.

Thank you