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**Matlab / Re: How do I solve two Ordinary Differential equations using Matlab**

« **on:**June 07, 2012, 02:45:03 AM »

Now, i am needing to solve equations system:

1.05*x" + 1.155*x' + 133.333*x + 0.043*y" = 0

0.86*x" + y" + 0.254*y' + 161.333*y = 0

With conditions: x(0) = 0.015; x'(0) = 0;

I has used commands as:

>> a = 1.05;

>> b = 1.155;

>> c = 133.333;

>> d = 0.043;

>> e = 0.86;

>> f = 1;

>> g= 0.254;

>> h = 161.333;

>> syms x y t;

>> [x,y] = dsolve('a*D2x + b*Dx + c*x + d*D2y = 0, e*D2x + f*D2y + g*Dy + h*y = 0' , 'x(0) = 0.015,Dx(0)=0' , 't')

but error, i don't know why, i hope that everyone can help me. Thank you so much

1.05*x" + 1.155*x' + 133.333*x + 0.043*y" = 0

0.86*x" + y" + 0.254*y' + 161.333*y = 0

With conditions: x(0) = 0.015; x'(0) = 0;

I has used commands as:

>> a = 1.05;

>> b = 1.155;

>> c = 133.333;

>> d = 0.043;

>> e = 0.86;

>> f = 1;

>> g= 0.254;

>> h = 161.333;

>> syms x y t;

>> [x,y] = dsolve('a*D2x + b*Dx + c*x + d*D2y = 0, e*D2x + f*D2y + g*Dy + h*y = 0' , 'x(0) = 0.015,Dx(0)=0' , 't')

but error, i don't know why, i hope that everyone can help me. Thank you so much