# not able to find solution for a system of differential equation

Posted 9 years ago
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 Hi, Mathematica 10 not giving any output to the following system of equation and returns the input as output Help required
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Posted 9 years ago
 Looks like Mathematica can't solve it symbolically. Complex differential equations frequently don't have symbolic solutions.
Posted 9 years ago
 Dsolve[{((x''[t])/(2*x[t]))+((y[t])/(4*(x[t])^3))+(((x'[t])^2)/(4*(x[t])^2))-((y''[t])/(2*y[t]))-(((y'[t])^2)/(4*(y[t]^2)))==0,((3*x''[t])/(2*x[t]))-(((x'[t])^2)/(4*(x[t])^2))-((y[t])/(2*(x[t])^3))+((y''[t])/(2*y[t]))-((3*((y'[t])^2))/(4*(y[t]^2)))+((2)/(x[t]*y[t]))-((x'[t]*y'[t])/(x[t]*y[t]))==0},{x,y},t] 
Posted 9 years ago
 It would be better to put your code in a "code sample" block, using the first icon under "reply to this discussion". Putting code in as text can result in errors. I speak from experience.
Posted 9 years ago
 Here is the equation I typed DSolve[{((x''[t])/(2*x[t]))+((y[t])/(4*(x[t])^3))+(((x'[t])^2)/(4*(x[t])^2))- ((y''[t])/(2*y[t]))-(((y'[t])^2)/(4*(y[t]^2)))==0, ((3*x''[t])/(2*x[t]))-(((x'[t])^2)/(4*(x[t])^2))-((y[t])/(2*(x[t])^3))+((y''[t])/(2*y[t]))- ((3*((y'[t])^2))/(4*(y[t]^2)))+((2)/(x[t]*y[t]))-((x'[t]*y'[t])/(x[t]*y[t]))==0},{x,y},t] 
Posted 9 years ago
 these are nonlinear coupled second order ODE. Most non-linear ode's do not have closed form solution. (the ticks on your screen shot look strange. But may be this is copy/paste. It is better to post plain text code here. not screen shot assuming you want someone to copy and try what you have there. You might want to try numerical solution.