Groups and FieldsEasyA Gallery of Groups ShareA Gallery of Groups · Easy problemDo A=(1101)A=\begin{pmatrix}1&1\\0&1\end{pmatrix}A=(1011) and B=(2001)B=\begin{pmatrix}2&0\\0&1\end{pmatrix}B=(2001), both in GL(2,R)GL(2,\mathbb R)GL(2,R), commute — that is, does AB=BAAB=BAAB=BA?AYes, AB=BAAB=BAAB=BABOnly if the matrices are both diagonalCNo, AB≠BAAB \ne BAAB=BADOnly if detA=detB\det A=\det BdetA=detBCheck Show answer Walk through it step by step Practice more like this Review this concept