Poisson brackets little problem

[fluidistic]

Homework Statement

For a particle, calculate Poisson brackets formed by:
1)The Cartesian components of the linear momentum \vec p and the angular momentum [/itex]\vec M =\vec r \times \vec p[/itex].
2)The Cartesian components of the angular momentum.

Homework Equations

[u,p]_{q,p}= \sum _k \left ( \frac{\partial q }{\partial q_k } \frac{\partial v }{\partial p _k} -\frac{\partial q }{\partial p_k } \frac{\partial v }{\partial q _k} \right ).

The Attempt at a Solution

2)Nothing still, waiting to complete 1).
1)I calculated the Cartesian components of M and p.
I don't understand what I have to calculate. [\vec p, \vec M] I'm guessing but with what subscript?
Thanks for any help.

Edit: Hmm I think the subscript is always q,p. But p and M are vectors, so have I to calculate directional derivative?

 

[sgd37]

\vec{p} = ( p_x , p_y , p_z ) = p_i and \vec{r} = ( x , y , z ) = x_i

M_i = \epsilon_{ijk} x_j p_k where the einstein summation convention is used

[p_i,M_j]= \sum _l \left ( \frac{\partial p_i }{\partial q_l } \frac{\partial M_j }{\partial p _l} -\frac{\partial p_i }{\partial p_l } \frac{\partial M_j }{\partial q _l} \right )

hope this helps