Nonlinear first-order differrential equation

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SUMMARY

The discussion focuses on solving the nonlinear first-order differential equation defined by m*dv/dt = -mg - kv^2, where m, g, and k are constants. The user initially solved the homogeneous equation m*dvh/dt = -kvh^2, yielding the solution vh = m/(kt - cm). However, attempts to substitute v = f(t)*vh into the original inhomogeneous equation resulted in a more complex differential equation for f(t), indicating the challenges associated with nonlinear equations. The user also explored variable separation techniques without success.

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Homework Statement



m*dv/dt = - mg - kv^2, where m,g and k are constants and v(t) is what I should solve

Homework Equations





The Attempt at a Solution


At first I solved homogeneous equation m*dvh/dt = -kvh^2 and got vh = m/(kt - cm). Where c is also constant.
Then I treid to get one solution for the original inhomogeneous equation by subtituting v = f(t)*vh = f(t)*m/(kt - cm) in the original equation, but by it I only got a more difficult differential equation for f(t). So it didn't work.

I also tried a few different subtitutions at the beginning with no success.
 
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You could separate the variables such as:

dy/dx = f(y)

integral (dy/f(y)) = integral(dx)

Initial condition determines integration constant.
 

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