Why is it enough to only check if $A\cdot A^{-1} = I$ when showing that $A^{-1}$ is the inverse of A?
3301
If $AB = I$ then $BA = I$
140459
Why is $\left(e^{2\pi i}\right)^i \neq e^{-2 \pi}$?
154133
Flawed proof by induction that $a^{n-1}=1$
10024
How to prove $(f \circ\ g) ^{-1} = g^{-1} \circ\ f^{-1}$? (inverse of composition)
108633
Why $f^{-1}(f(A)) \not= A$
19962
Why is $\infty \cdot 0$ not clearly equal to $0$?
146093
Why if $n \mid m$, then $(a^n-1) \mid (a^m-1)$?
46698
Showing a set is closed under inverses
130854
Constructing example showing $\mathbb{E}(X^{-1})=(\mathbb{E}(X))^{-1}$
154596
When should \cdot be used to indicate multiplication?
78736
Check my proof that $(ab)^{-1} = b^{-1} a^{-1}$
5526
Prove that $ℤ[i]^*= \{1,-1,i,-i\}$
114346
Why is $a^{-1}$ mod $p$ equal to $a^{p-2}$ mod $p$?
82097
If $A \succeq B$, is it true that $B^{-1} \succeq A^{-1}$?
57780
$\sum_{i=1}^n i\cdot i! = (n+1)!-1$ By Induction
103223
If $x^a$ is $x$ multiplied $a$ times, then how does $x^{-1}$ make sense?
121663
If $a$ is a zero divisor of $\mathbb{F}$, then does $a$ fail to have a multiplicative inverse?