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Separable Equations

The general solution to this equation is found by separation of variables.
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Even when variables can be separated, the final solution might be accompanied by a warning message from Solve, or it might only be given as an InverseFunction object.
Solving this ODE generates a warning message because Solve obtains an expression for y[x] using Log, the inverse of Exp. This warning message can be ignored.
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The solution to this equation is given as an InverseFunction object, in order to get an explicit expression for y[x].
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