Show that if matrix $X$ satisfies the relation $X \cdot Y = Y \cdot X$ it has a specific form
120937
Matrices that commute with all matrices
104068
Prove that $\forall a,b\in\mathbb{C} \exists c,d \in \mathbb{C}: c+d = a \land cd = b$
117769
How to show that the determinant of this matrix is in a nice product factorization,
37985
Show that $|x|^2 = |y|^2$ with $A$ orthogonal and $Ax = \cos (θ)x − \sin (θ)y$, $Ay = \sin (θ)x + \cos (θ) y$
90345
If $\lVert x\rVert=\lVert y \rVert$, prove that exists a unitary transformation such as $Tx=y$
39746
How to prove that given set is a connected subset of the space of matrices?
63119
Let $M=\big( \begin{smallmatrix} A & B \\ C & D \end{smallmatrix} \big)$. Prove $\det(M)=\det(A)\cdot \det(D-C·A^{-1}·B)$.
155974
Show $||Tx||_2 \leq ||(v_n)||_2 \cdot ||x||_{\infty}$
122305
Proof of matrix norm property: submultiplicativity
138931
Show that $||x+y||\cdot||x-y||\le||x||^2+||y||^2$
15452
Proving determinant product rule combinatorially
72920
$x \perp y$ if and only if $\Vert x + \alpha y \Vert \ge \Vert x \Vert$ for all scalars $\alpha$
110484
Condition on a matrix so that its determinant is $2$
37537
Show that $det(A)=0$ for a Matrix $A$ Such That for $X=[2,3,4]^{T}$, $AX=0$
5616
How can I prove the IFF condition for this group of matrices?
3820
Prove that $||x|-|y||\le |x-y|$
76335
Proving that two matrices are congruent, in order to establish a rank and signature result.