Question: how to a convergent solution

I wrote an equation and intended to iterate P(r) till that value of r when P(r) becomes 0.what is the value of r for which P(r)=0, and also  obtained its convergent decreasing graph which show convergence of P(r) to 0.
 

restart

NULL

G := 6.6743*10^(-8);

0.6674300000e-7

 

0.2997924580e11

 

0.7321400000e36

(1)

``

sys2 := diff(P(r), r) = -G*(epsilon+P(r))*((8.98*10^14*(1/3))*Pi*r^3+4*Pi*r^3*P(r)/c^2)/(c^2*(r^2-(2*G*r*(8.98*10^14*(1/3))*Pi*(r^3))/c^2)), P(0.1e-9) = 8.5561*10^34

diff(P(r), r) = -0.7426160269e-28*(0.7321400000e36+P(r))*(0.2993333333e15*Pi*r^3+0.4450600224e-20*Pi*r^3*P(r))/(r^2-0.4445794614e-13*r^4*Pi), P(0.1e-9) = 0.8556100000e35

(2)

``

``


 

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