Hello, I have a simple question. Lets say we have a mechanical system with 2 degrees of freedom. Say the generalized coordinates (which are independent from each other in terms of constraints) are [tex]x[/tex] and [tex]y[/tex]. When we solve Lagrange-Euler equations for this system, we get time evolutions of coordinates as functions of time: [tex]x(t)[/tex] and [tex]y(t)[/tex]. I am wondering what the partial derivative of x with respect to y would be. this would not be 0, right?