exponential representation of 3 dimensional rotations

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This is a problem I am stuck at. I can't find appropriate matrices for a). They must be linked to Pauli matrices but I can't find a way to extend Pauli matrices to 3 dimensional space. Could anyone suggest me what the matrices are?

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Hint: For the first one, the matrix is \begin{pmatrix} 0 & 0 & 0 \\ 0 & 0 & -1 \\ 0 & 1 & 0 \end{pmatrix}

Now you have to work out why exp of that really is the thing you want, and do the rest.

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Well, $$iL_1=\pmatrix{0&0&0\\0&0&-1\\0&1&0}.$$ I'll leave you to work out the others. (Why do physicists have to strew everything with $i$s?)