Annihilator of image $T$ equals to $\text{ker}(T^*)$
359
Show that $\ker \hat{T} = \text{ann}(\text{range } T)$
140711
Linear independence of images by $A$ of vectors whose span trivially intersects $\ker(A)$
76694
Proving that $UT=TU$ iff $U=g(T)$ for some polynomial $g$
32443
Find the kernel of a ring homomorphism $f(x)\to f(\sqrt 2)$
98949
Subspaces and annihilators
71822
Commutator algebra in exponents
52642
Show that $\text{C}/c \cong (c/(\text{C}^{\text{op}}))^{\text{op}}$
58741
Operator Exponential $e^A e^B = e^{A+B}$
76685
Determine $\text{Aut}(S)$ where $S = \mathbb{Q}[x]/(x^2)$
67058
Prove that $\text{rank}(X^TX)=\text{rank}(X)$
28565
Prove $\operatorname{rank}A^TA=\operatorname{rank}A$ for any $A\in M_{m \times n}$
36747
$\text{Tor}_0^R(M,N)\simeq M\otimes_R N$
88841
annihilator linear algebra
75059
Let $T:\mathbb{R}^n\to \mathbb{R}^n$ be a linear transformation...
117131
Canonical Isomorphism Between $\mathbf{V}$ and $(\mathbf{V}^*)^*$
15300
How to show that $(W^\bot)^\bot=W$ (in a finite dimensional vector space)
147888
Show that $M=\bigcap_{\mathfrak{p}\in\operatorname{Spec}(R)}M_\mathfrak{p}=\bigcap_{\mathfrak{m}\in\text{Max}(R)}M_\mathfrak{m}$ for certain $M$.