Initial Conditions Applied to a Lagrangian

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vs74043
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Homework Statement



The scenario is a pendulum of length l and mass m2 attached to a mass of m1 which is allowed to slide along the horizontal with no friction. The support mass moves along in the X direction and the pendulum swings through the x-y plane with an angle θ with the vertical. After finding the Lagrangian and the Euler-Lagrange equations for each of the two variables X and θ, apply the conditions
$$\theta(0)=\theta_{0}<<1\text{ but greater than 0}\\
\dot{\theta}(0)=0\\
X(0)=0\\
\dot{X}(0)=0$$
to get the motion for θ and X.

Homework Equations


I have derived the Lagrangian of this to be
$$L=\frac{1}{2}(m_{1}+m_{2})\dot{X}^{2}+m_{2}l\cos\theta\dot{\theta}\dot{X}+\frac{1}{2}m_{2}l^{2}\dot{\theta}^{2}+m_{2}gl\cos\theta$$

The Attempt at a Solution

 
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Hello vs, :welcome:

Post needs some adjusting to the PF guidelines. What relevant equations do you have to continue this exercise ? What you mention now is an intermediate result (which I think is right, but I didn't check it - will do so if you show the steps :smile: ).