How to show that upper triangular matrices form a subgroup?
138297
Let $G = GL_2\mathbb (R)$. Show that $T$ is a subgroup of $G$
41231
Subgroups of (Z,+) of order n
146760
Prove that H is a subgroup of G
131516
Subgroup generated by n-th powers of elements
7575
Show the commutator subgroup of $S_{n}$ is $A_{n}$ for $n \geq 5$
103829
Find the subgroups of A4
73155
Prove that for any square matrix, an invertible matrix B exists, so that BA is triangular
90584
Show set of affine transformations is a group
5616
How can I prove the IFF condition for this group of matrices?
152825
what are all the open subgroups of $(\mathbb{R},+)$
147298
How to find all subgroups of a direct product?
144531
How to prove that a nilpotent operator has a basis representation that is strictly upper triangular?
47824
Calculation of subgroups of $(Z_{12}, +)$
89047
If a matrix is triangular, is there a quicker way to tell if it is can be diagonalized?
2064
Finite subgroups of orthogonal transformations in $\mathbb{R}^3$
142607
Upper triangular matrix with big zero in lower triangular?
108975
The simple modules of upper triangular matrix algebras.