How can I solve this second order differential equation?

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SUMMARY

The discussion focuses on solving the second-order differential equation derived from the system of equations dx/dt=1-1/y and dy/dt=1/(x-t). The key transformation involves recognizing that the equation can be rewritten as y'' - (1/y)(y')² = 0. The solution approach suggested includes substituting y with the exponential form y = Ae^(Bt) to determine the constants A and B, which are essential for finding the general solution.

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Homework Statement



dx/dt=1-1/y
dy/dt=1/(x-t)

The Attempt at a Solution



If I take the derivative of the second equation and substitute it to the first one I

\frac{d^2 y}{dt^2} - \frac{1}{y} (\frac{dy}{dt})^2 = 0

but I don't know how to solve this. Could anyone name any methods that could try?
Thanks.
 
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The trick is to notice
<br /> y&#039;&#039;-\frac{1}{y}(y&#039;)^{2}=0\Rightarrow\frac{y&#039;&#039;}{y&#039;}=\frac{y&#039;}{y}<br />
 
<br /> y&#039;&#039;-\frac{1}{y}(y&#039;)^{2}=0\Rightarrow yy&#039;&#039;= y&#039;^{2}

Now put in the equation y=Ae^{Bt} and find A and B.
 

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