Is it true $ABA=A \Rightarrow BAB=B$?
3330
Square matrices, ABA = A?
136448
$ABAB=0_{n\times n}$, then must $BABA$ be $0_{n\times n}$?
99631
Prove/Disprove: Find $a\in S_4$ that is not a power of $b$ such that $ab=ba$ while $b=(123)$
43570
Finding two non-zero matrices where $AX = BA$
108084
Is it always true? $\left|A-B\right| \le \left|A\right| + \left|B\right|$
138283
$|(a,b)| = |\Bbb R|$ ? Cardinality of any open interval
41044
Equivalence of $a \rightarrow b$ and $\lnot a \vee b$
33542
When is $A- B = B- A$?
86030
Prove or disprove - If a divides b and b divides a does a=b
139934
In $\mathbb{Z}/(n)$, does $(a) = (b)$ imply that $a$ and $b$ are associates?
37061
The order of $ab$ when $a,b$ commute
89177
$\operatorname{adj}(AB) = \operatorname{adj} B \operatorname{adj} A$
53113
$I-AB$ be invertible $\Leftrightarrow$ $I-BA$ is invertible
89190
Why is it true that $|AB:A|=|B:A\cap B|$ even if $A$ is not normal in $AB$? (Second Isomorphism Theorem)
59397
Eigenvalues of $AB$ and $BA$ where $A$ and $B$ are square matrices
31783
Is this proof of $ab = 0$ correct?
12927
$A^2+B^2=AB$ and $BA-AB$ is non-singular