Can the Lagrangian equation be simplified using the operator relation?

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SUMMARY

The discussion focuses on the simplification of the Lagrangian equations, specifically the equation {d\over dt}\left(\frac{\partial T}{\partial \dot{q_j}}\right) - \frac{\partial T}{\partial q_j} = Q_j. Participants demonstrate that this can be reformulated as \frac{\partial \dot{T}}{\partial \dot{q_j}} - 2\frac{\partial T}{\partial q_j} = Q_j by utilizing the operator relation \frac{d}{dt} \frac{\partial}{\partial x} = \frac{\partial}{\partial x} \frac{d}{dt}. This transformation is confirmed to be valid, providing a clearer perspective on the dynamics described by the Lagrangian mechanics.

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Reshma
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Show that the Lagrange equations of the form
[tex]{d\over dt}\left(\frac{\partial T}{\partial \dot{q_j}}\right) - \frac{\partial T}{\partial q_j} = Q_j[/tex]
can also be written as
[tex]\frac{\partial \dot{T}}{\partial \dot{q_j}} - 2\frac{\partial T}{\partial q_j} = Q_j[/tex]

Well it can be easily show that:
[tex]{d\over dt}\left(\frac{\partial T}{\partial q_j \right)} = \frac{\partial \dot{T}}{\partial {q_j}}[/tex]
Using the operator relation:
[tex]\frac{d}{dt} \frac{\partial}{\partial x} = \frac{\partial}{\partial x} \frac{d}{dt}[/tex]

Can this be applied here?
 
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