Problem with Lagrange first kind equations

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Homework Statement


Two masses move in a plane restricted to concentric circles with radii R1 and R2. They are joined by a solid rod of length B. Use Lagrange first order equations to find the equilibrium point


Homework Equations


Constraint due to the solid bar: B = R12 + R22 -2R1R2cos(θ1 + θ2), where θ1 and θ2 are the polar coordinates of the masses.

The Attempt at a Solution


My Langrangian is as follows: L = (m/2)(R12ω12+R22ω22)-mg(sinθ1+sinθ2)
By substituing in this expression http://en.wikipedia.org/wiki/Lagrangian_mechanics#Lagrange_equations_of_the_first_kind I find two equations of motion:
-mgcos(θ1)+mR12+α1 + R1R2sin(θ1 - θ2)λ1 = 0
-mgcos(θ2)+mR22+α2 - R1R2sin(θ1 - θ2)λ2 = 0
where α1 and α2 are the angular accelerations of the masses, and the λs are the Lagrange multipliers. I can't solve this equations, though. Is there any method of solving them that I cannot find or is it that my whole procedure is wrong?
 
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Can you show us what your Lagrangian looks like, that you use to derive these equations of motion?
You denoted the constraint by ##L##, but I don't think that expression is your Lagrangian because I don't see a kinetic term.
 
Sorry, its a bit confusing because the length of the bar is L. I'll change it to B and edit the rest.
 
To solve this, I first used the units to work out that a= m* a/m, i.e. t=z/λ. This would allow you to determine the time duration within an interval section by section and then add this to the previous ones to obtain the age of the respective layer. However, this would require a constant thickness per year for each interval. However, since this is most likely not the case, my next consideration was that the age must be the integral of a 1/λ(z) function, which I cannot model.
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