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0answers
65 views

How to eliminate functions from a set of differential equations with Maple?

I've got a set of 7 equations, 3 of them being differential equations, with 7 unknown functions. I'd like to reduce the system to a set of 2 differential equations by eliminating 5 of the unknown ...
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1answer
40 views

Solving an ODE in Maple via Picard approximations

I am trying to use Maple to apply Picard approximations to the following ODE: $$ 2xyy' + x^2 - y^2 = 0,\ y(0) = 1 $$ I transformed it into the form $y' = f(x, y)$: $$ y' = \frac {y^2 - x^2} {2xy} ...
0
votes
1answer
25 views

Finding zeroes of a numerical solution of an ODE in Maple

I have a system of ODEs involving many variables, say 20, and I have solved this system numerically by Maple for a particular initial condition. When I plotted these solutions it was clear that ...
1
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1answer
31 views

defining ODEs recursively in maple

I want to numerically look at a system of ODEs with a large number of variables; defined by $da_j(t)/dt= 2^j a_{j-1}^2 - 2^{j+1} a_j a_{j+1}$, for $j=0\ldots50$ with $a_{-1}= a_{51}=0$. In maple, I ...
1
vote
1answer
44 views

keeping track of a quantity in an ODE system

I have looked at some Maple help documents, but it was hard to find what I wanted to do.. My situation is quite simple. I have a couple ODE for (say) 5 variables, $a_1 '(t) = a_2 (t) a_3(t) - a_1 ...
0
votes
0answers
61 views

SIR models - help!

I am doing a project on the spread of infectious diseases and I have chosen to model this spread by using the SIR model - (susceptibles, infectious, recovered). I have to insert data into this model ...
0
votes
1answer
53 views

Have trouble making a phase line plot with Maple.

Draw the phase line, and sketch several graphs of solutions in the $ty$-plane Is the directions for my homework. I have tried the Phase Portraits for Autonomous Systems under tasks, but I don't ...
0
votes
1answer
57 views

How to plot this direction field in Maple.

$y^{\prime}=ay+b$ where $a,b$ are positive numbers. I know how to plot this if I have exact values for both $a$ and $b$, but how to see the difference as either/both $a$ and $b$ change? I ...
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1answer
53 views

Is there an analitical solution for such ODE $$ \frac{d y(x)}{dx}=\frac{a*y(x)^3+b}{c* y(x)^3+ d} $$

I have an ODE $$ \frac{d y(x)}{dx}=\frac{a*y(x)^3+b}{c* y(x)^3+ d} $$, $$a,b,c,d - const$$ And I would love to solve it analitically. I tred maple 15 and 17 and got $$ y \left( x \right) =1/2\,{ ...
2
votes
2answers
178 views

ODE-system solving with initial conditions (Maple)

This is my problem: I have to solve a differential-equation-system, and then to plot the results. The system is : { S'=-r*S*J, J'=r*S*J-a*J, R'=a*J }. It's about epidemiology, S, J, and R are ...
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1answer
77 views

SIR Models - interpretation (epidemiology) - help!

I am doing a project on modelling the spread of diseases and am using a SIR (susceptible, infected and recovered) model to do so. I need help interpreting this plot: What does this plot say about ...
1
vote
0answers
91 views

Change of variables in differential equation in Maple

Consider the differential equation $zZ'' + Z' + \alpha^2Z = 0, $where $Z = Z(z).$ Use the change of variables $x = \sqrt{z/a}$ with $a$ a constant to obtain the differential equation $Z'' + (1/x)Z' ...
1
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1answer
63 views

solving the pde $U_t(x,t)=U_{xx}(x,t)-b(t)U(x,t)+q_0$ for $U(x,t)$ using maple

I have the pde $U_t(x,t)=U_{xx}(x,t)-b(t)U(x,t)+q_0$, where $b(t)$ is a function of only $t$ and $q_0$ is a constant, $0<x<\pi$, $t>0$. I also have some boundary conditions: $U(x,0)=0$ and ...
1
vote
2answers
119 views

How use Maple12 to solve a differential equation by using Euler's method?

Consider the differential equation $y^{\prime}=y-2$ with initial condition $y\left(0\right)=1$. a) Use Euler's method with 4 steps of size 0.2 to estimate $y\left(0.8\right)$ I know how to do this ...
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1answer
1k views

Solving System of Differential Equations with initial conditions maple

I've been asked to solve a system of differential equations using maple (for practice, as it is solvable by hand...), but I seem to be running into goop with syntax... d/dt r(t) = -lambda_r*r(t) + ...
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1answer
132 views

Maple plot problem

I'm tryin to make a 3D plot of a differential-equation. I already found: $$\begin{align*} &x_1' = f(t) x_4 - x_2\\ &x_2' = -f(t) x_3 + x_1\\ &x_3' = f(t) x_2 + x_4\\ &x_4' = -f(t) x_1 ...
1
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1answer
137 views

How to numerically solve such differential system (ODE, Nonstationary, Nonhomogeneous) (what steps to take)?

So I have next system with boundary conditions: Maples sol:=dsolve([sysG, bc]) and ...
1
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0answers
184 views

maple code for exp-func. for solving PDE's & non-linear ODE's?

How can I create the Maple code using exponential-function solving the equation below? $u_t = \gamma u_x+6u(u_x)^2+(3u^2-1)u_{xx}-u_{xxxx}$ $u_t =u_{xx}-u^3+u,$ $\alpha u''(x) = \beta ...
2
votes
1answer
172 views

Numerical solution of fractional integro-diffrential equ. using collocation method?

problem comes from "Numerical solution of fractional integro-differential , equations by collocation method , E.A. Rawashdeh, Department of Mathematics, Yarmouk University, Irbid 21110, Jordan" ...
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votes
0answers
93 views

How can I use rationalized haar functions to solve differential equations?

How can I use rationalized haar functions to solve differential equations? I do not have any idea what are haar functions and how to use them please help!
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0answers
170 views

How to derive to inverse z transform of $\sqrt{\frac{1-a^2}{1-\frac{a}{z}}}$ from Laguerre differential equation?

How can I derive the inverse z-transform of: $$\sqrt{\frac{1-a^2}{1-\frac{a}{z}}}$$ If Maple is not the way, how to derive manually? With Maple code I encounter some problems ...
2
votes
1answer
1k views

A series solution of the differential equation: $\frac{d^2u(x)}{dx^2}+ u(x)^n = 0.$

Consider the differential equation $\frac{d^2u(x)}{dx^2}+ u(x)^n = 0.$ Let the solution be $u(x) = u_0(x) + p u_1(x) + p^2u_2(x) + \cdots +p^m u_m(x).$ Now we are interested in substituting the ...
0
votes
1answer
2k views

System of differential equations in Maple

I have problems entering a system of differential equations to Maple 13. Equations are: $x' = -4x + 2y$ $y' = 5x - 4y$ Solve for $x = 0, y = 0$ Thank you in advance
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1answer
158 views

Differential equation problem in Maple

I have differential equation $x\cdot\sqrt{4+y^2}\,dx + y\cdot\sqrt{1+x^2}\,dy = 0$, which is simple to solve on paper, but I have problem solving it with Maple (I use 10th, tried on 14th also). When ...