Differential Equations Help, non-linear first order with substitution

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SUMMARY

The discussion focuses on solving the non-linear first-order differential equation (r^2)(dT/dr) + B*r*T = T^2, with the initial condition dT/dr |r=0 = 0. The user successfully transformed the equation into the form dT/dr = -BT/r + T^2/r^2 and applied the substitution λ = T/r, leading to the equation r * dλ/dr + λ = -Bλ + λ^2. The main challenge discussed is how to separate variables to continue solving the equation.

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leomclaughlin
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(r^2) (dT/dr)+B*r*T=T^2, with initial condition dT/dr |r=0 =0 where B is a constant


I've gotten it to this:

dT/dr = -BT/r + T2 / r2

by dividing everything by r2, then I substitute using λ= T/r which gives:


r * dλ/dr + lambda = -B * (λ) + λ^2


I don't know how to separate from here, any help is appreciated
 
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## r \frac{d\lambda}{dr} + \lambda = -B\lambda + \lambda^{2} \Rightarrow \frac{1}{-\lambda(B+1) + \lambda^{2}} \frac{d\lambda}{dr} = \frac{1}{r} ##
 

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