SE(3)\mathrm{SE}(3) is the group of orientation-preserving Euclidean isometries of R3\mathbb R^{3}. Each element is x↦Ax+bx\mapsto Ax+b with A∈SO(3,R)A\in\mathrm{SO}(3,\mathbb R) and b∈R3b\in\mathbb R^{3}, and

(A,b)(A′,b′)=(AA′,Ab′+b).(A,b)(A^{\prime},b^{\prime})=(AA^{\prime},Ab^{\prime}+b).
Dimensions and structure

This group has real dimension 66. This gives the of translations by the indicated .

Direct verification

The determinant-one condition is preserved by composition and inversion. Its has a skew-symmetric block and an arbitrary translation vector, giving n(n−1)/2+n dimensions.