Finding weights and friction in a static pulley system using Lagrange's equation

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TheDestroyer
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Hi guyz, I taked the picture attached with my mobile directly from the book, please help me to find the weights of A,B (not masses), and the friction coefficient (f) for A on the Horizontel plane, and note, the rope isn't able to change lenght, System is static, A,B are equal, weight of K is Q

NOTE : I NEED TO FIND THE SOLUTION OF THIS SYSTEM USING THE ANALYTICAL MECHANICS AND LAGRANGES EQUATION (NOT THE NEWTONIAN VECTOR MECHANICS)

The Answer is:
[tex]P_A = P_B = \frac{Q}{2}[/tex]
[tex]f=1[/tex]

Lagranges equation:

[tex]\frac{d}{dt} \frac{\partial L}{\partial \dot{q}} - \frac{\partial L}{\partial q} = 0[/tex]

[tex]L = T - u[/tex]

L is the langrangian, T is kinetic energy, u is potential energy, q is generalized coordinate,
 

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First, how many degrees of freedom are there?
Second, what generalized variables would you like to define?
 
Only what i have written, i don't know how many freedom degrees, the question has only the information A = B, K weight is Q, and that diagram,

I'M NERVOUS OF THAT PROFRSSOR, HE MADE THAT BOOK STUPIDLY, IF YOU SAW IT YOU WILL KILL HIM, NOTHING IS CLEAR !
 
Well? No one answered! Should we say I have fools book?