If $D$ is a field then every matrix of $\mathrm{SL}_m(R)$ can be written as product of elementary matrices for $m$ not equal to 2, because for $m=2$ Cohn gives an example which contradict this result. For $\mathrm{GL}_m(R)$ how you can say?
If $D$ is a field then every matrix of $\mathrm{SL}_m(R)$ can be written as product of elementary matrices for $m$ not equal to 2, because for $m=2$ Cohn gives an example which contradict this result. For $\mathrm{GL}_m(R)$ how you can say?
