Solving the Ordinary Differential Equation

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Yeahh 2018-11-15

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编辑： madhan ravi 2018-11-15

I am not sure how to solve these systems of differential equation. However, the final graph representation of the result is two exponential curves for

and

in respect to time.

Also, with

, the variable ks and BP are all constant.

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madhan ravi 2018-11-15

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编辑：madhan ravi 2018-11-15

在 MATLAB Online 中打开

EDITED

use dsolve()

Alternate method using ode45:

Screen Shot 2018-11-15 at 11.17.17 AM.png

tspan=[0 1];
y0=[0;0];
 
[t,x]=ode45(@myod,tspan,y0)
plot(t,x)
lgd=legend('Cp(t)','Cr(t)')
lgd.FontSize=20
 
function dxdt=myod(t,x) 
tau=2;
ks=3;
BP=6;
k1=5;
k2=7;
x(1)=exp(-t)/tau; %x(1)->Cp
dxdt=zeros(2,1); 
dxdt(1)=k1*x(1)-(k2/(1+BP))*x(2); %x(2)->Cr
dxdt(2)=k1*x(1)-k2*x(2);
end

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Yeahh 2018-11-15

编辑：madhan ravi 2018-11-15

Thank you so much, I have one last question.

What doest this line means?

dxdt=zeros(2,1);

madhan ravi 2018-11-15

编辑：madhan ravi 2018-11-15

Anytime :), It is called preallocation(please google it) imagine as a container to store something. Make sure to accept for the answer if it was helpful.

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