A A system of DEs with variable coefficients.

inertiagrav
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Hi. I have been trying for sometime to solve the following system of DEs analytically(Is it possible?) but no luck so far.
$$x''(t)=-z(t)x'(t)-x(t)+y(t),$$ $$y'(t)=-z(t)y(t)+x^2(t)$$ $$z'(t)=-2z^2(t)-x(t)$$.

With the initial conditions ##x(0)=1## , ##x'(0)=0## ,##y(0)=0## and ##z(0)=1##.

Thanks a lot in advance.
 
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Hello, thanks for your responses. I solved it numerically in Mathematica before posting it here, even for different sets of initial conditions. I am trying to get an approximate analytical solution and yea, i will ask for a context regarding the equations. Our Professor did say that if needed we can neglect the ##x^2(t) ## term in ##y'(t)## but i still don't see how i can solve it.
 
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