Find elements $f,g\in\mathrm{End}(V)$ such that $f\circ g=id_V$ and $f,g\not\in \mathrm{End}(V)^{\times}$
72507
Does $ab=1$ imply $ba=1$ in a ring?
51695
Finding all homomorphisms between $\mathbb{Z}/m\mathbb{Z}$ and $\mathbb{Z}/n\mathbb{Z}$
95686
$Lie(G \times H)\cong Lie(G)\oplus Lie(H)$
134840
Generators and relations for $\text{PSL}(2, \mathbb{F}_q)$
34712
Decomposable elements of $\Lambda^k(V)$
80684
Counter example for $(A \times B) \cap (C \times D) = (A \cap C ) \times (B \cap D)$
154001
$(g\circ f)^{-1}=f^{-1}\circ g^{-1}$
114662
Construction of a specific non-commutative and infinite group (with conditions on the order of the elements)
154117
Showing $[(fg)h]_n = [f(gh)_n]$ in the linear algebra $F^\infty$
52354
Given a idempotent endomorphism, show that $M = \ker(f) \oplus \ker (f-\text{id}_M)$
154142
Finding a specific basis for an endomorphism
46687
Elements of $GL_{2}(\mathbb{Z})$ of finite order
74924
identity element of $(D_n ,\gcd)$
89659
$H_1 ,H_2 \unlhd \, G$ with $H_1 \cap H_2 = \{1_G\} $. Prove every two elements in $H_1, H_2$ commute
113022
Is the graph $G_f=\{(x,f(x)) \in X \times Y\ : x \in X \}$ a closed subset of $X \times Y$?
115299
Elements of $\mathbb{F}_p$ having cube roots in $\mathbb{F}_p$
148668
How to show $A\times (B\cup C) = (A\times B)\cup (A\times C)$