Unable to solve a nonlinear DE analytically help needed

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motavassely
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Hi all,

I have a nonlinear differential equation and I need to find an analytic solution for it. Here it is:

\ddot{S}=-{1 \over 6} \dot{S}-{2 \over 7}(1-S)^2(- \dot{S})^{1.3}

I have used a transformation to simplify it:

-\dot S = v

and came up with this DE which I couldn't solve it:

{{dv} \over {dS}} ={1 \over 6} - {2 \over 7} (1-S)^2 v ^ {0.3}

Anyone who can solve them?

Bests,

Ali
 
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shouldnt you have

{{dv} \over {dS}} ={1 \over 6}v - {2 \over 7} (1-S)^2 v ^ {0.3}
 
Unfortunately not. It's not a Bernoulli? DE.
 
motavassely said:
Hi all,

I need to find an analytic solution for it.

S(t)=k
 
a bit more sophisticated solution, please!
 
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