The elements and its order of GL2(F2)

We write out all the elements of GL_2(\mathbb{F}_2) and compute the order of each element.

Solution. Recall that GL_2(\mathbb{F}_2) is the set of 2 \times 2 invertible matrices (i.e., their determinants are not equal to 0). Specifically, we get the next elements:
 GL_2(\mathbb{F}_2) = \{ \begin{pmatrix} 
1 & 0 \\
0 & 1
\end{pmatrix},  
\begin{pmatrix} 
0 & 1 \\
1 & 0
\end{pmatrix},
\begin{pmatrix} 
 1 & 1  \\
 1 & 0 
\end{pmatrix},
\begin{pmatrix} 
 1 & 1  \\
 0 & 1
\end{pmatrix},
\begin{pmatrix} 
 0 & 1  \\
 1 & 1
\end{pmatrix}, 
\begin{pmatrix} 
 1 & 0  \\
 1 & 1 
\end{pmatrix} \} 
Now we will determine for each matrix its order:
\begin{pmatrix} 
1 & 0 \\
0 & 1
\end{pmatrix}
has order 1. The following matrix:
\begin{pmatrix} 
0 & 1 \\
1 & 0
\end{pmatrix}
\begin{pmatrix} 
0 & 1 \\
1 & 0
\end{pmatrix} = 
\begin{pmatrix} 
1 & 0 \\
0 & 1
\end{pmatrix}
has order 2. The following matrix:
\begin{pmatrix} 
 1 & 1  \\
 1 & 0 
\end{pmatrix}
\begin{pmatrix} 
 1 & 1  \\
 1 & 0 
\end{pmatrix}
\begin{pmatrix} 
 1 & 1  \\
 1 & 0 
\end{pmatrix}
=
\begin{pmatrix} 
 0 & 1  \\
 1 & 1 
\end{pmatrix}
\begin{pmatrix} 
 1 & 1  \\
 1 & 0 
\end{pmatrix}
=
\begin{pmatrix} 
1 & 0 \\
0 & 1
\end{pmatrix}
has order 3. The following matrix:
\begin{pmatrix} 
 1 & 1  \\
 0 & 1 
\end{pmatrix}
\begin{pmatrix} 
 1 & 1  \\
 0 & 1 
\end{pmatrix}
=
\begin{pmatrix} 
1 & 0 \\
0 & 1
\end{pmatrix}
has order 2. The following matrix:
\begin{pmatrix} 
 0 & 1  \\
 1 & 1 
\end{pmatrix}
\begin{pmatrix} 
 0 & 1  \\
 1 & 1 
\end{pmatrix}
\begin{pmatrix} 
 0 & 1  \\
 1 & 1 
\end{pmatrix}
=
\begin{pmatrix} 
 1 & 1  \\
 1 & 0 
\end{pmatrix}
\begin{pmatrix} 
 0 & 1  \\
 1 & 1 
\end{pmatrix}
=
\begin{pmatrix} 
1 & 0 \\
0 & 1
\end{pmatrix}
has order 3. The following matrix:
\begin{pmatrix} 
 1 & 0  \\
 1 & 1 
\end{pmatrix}
\begin{pmatrix} 
 1 & 0  \\
 1 & 1 
\end{pmatrix}
=
\begin{pmatrix} 
1 & 0 \\
0 & 1
\end{pmatrix}
has order 2.

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