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Question: ODE system

Question:ODE system

bradders 32 Maple
plot student
March 01 2010
0

> eqn1 := diff(e(z)^2, z) = ((3/2)*e(z)^2-3*(v[0]*exp(-u*f(z)))^2/(2*(e(z)^2-O*(1+z)^(3*g)))+(1/2)*((g-1)*3)*O*(1+z)^(3*g))/(2*(1+z));
> eqn2 := diff(f(z), z) = sqrt(abs(1-(v[0]*exp(-u*f(z)))^2/(e(z)^2-O*(1+z)^(3*g))^2))/(e(z)*(1+z));
>
> eqn3 := subs(O = .27, g = 1, v[0] = .1, u = 0.5e-2, eqn1);
> eqn4 := subs(O = .27, g = 1, v[0] = .1, u = 0.5e-2, eqn2);
>
> sol1 := dsolve([eqn3, eqn4, f(0) = 1, e(0) = 1], numeric, maxfun = 1000000000);
> plots[odeplot](sol1, [[z, e(z), color = red]], 0 .. 2);
Warning, cannot evaluate the solution further right of .77942812, probably a singularity
 

why do i get this singularity, i cant find out!

need plot to go 0..2

 

cheers
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