If we are interested in a 3D rotation for an Arbitrary angle, we can instead use a rotation tensor. RijR_{ij}Rij = δij\delta_{ij}δij − dθd\thetadθ ϵijk\epsilon_{ijk}ϵijknkn_knk. Which is the rotation matrix for an infinitesimal angle dθd\thetadθ about a unit vector n\mathbf{n}n.
If we are interested in a 3D rotation for an Arbitrary angle, we can instead use a rotation tensor. Rij = δij − dθ ϵijknk. Which is the rotation matrix for an infinitesimal angle dθ about a unit vector n.