Apparently, this user prefers to keep an air of mystery about them.
10 Suppose $H \le G$ and $g^2\in H$ for all $g\in G$. Show $H$ is a normal subgroup of $G$ [duplicate] jul 25 '13
4 If every nonzero element of $R$ is either a unit or a zero divisor then $R$ contains only finitely many ideals. jul 17 '13
4 Proof of the uniqueness of maximal ideal may 21 '13
4 Show that the matrix $A+E$ is invertible. jul 8 '13