Deriving the square angular momentum in spherical coordinates

Raziel2701
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Homework Statement


I want to derive the square of the total angular momentum as shown here: http://en.wikipedia.org/wiki/Angular_momentum_operator#Angular_momentum_computations_in_spherical_coordinates


Homework Equations



The x,y, and z components of angular momentum are shown in the above link. I'm attempting to solve it by L^2=(L_x)^2 + (L_y)^2+(L_z)^2

The Attempt at a Solution


I think my problem is that I do not know how to deal with those partial differential operators. How do you go about squaring that binomial term that has differential operators? I think that's what I need to know and I don't know what to google to look for it.

Thank you.
 
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