If $T^k = Id$ for $k\ge 1$ then $T$ is diagonalizable
58476
Why can a matrix whose kth power is I be diagonalized?
52260
Diagonalization and eigenvalues
110325
proof of basic fact that torus actions are diagonalizable
151553
Big-O proof showing that t(n) is O(1)
68238
Diagonalisable or not?
5322
Let $A$ be a complex matrix such that $A^n = I$, show that $A$ is diagonalisable.
36613
Prove that simultaneously diagonalizable matrices commute
67784
If $A + A^t = 2I$ then $\det(A) \geq 1$
78307
Under what conditions is $AA^T$ invertible?
47653
Cantor diagonalization and fundamental theorem
77361
How to prove $|H|[K:K \cap (g^{-1}Hg)]=|K|[H:H \cap (gKg^{-1})]$?
116376
Prove the determinant is the product of its diagonal entries
62077
Prove that if $W_1\subseteq V$ finite-dimensional, then there is $W_2\subseteq V$ such that $V=W_1\oplus W_2$
34700
Proving that the matrix exponential map is surjective onto the general linear group
76694
Proving that $UT=TU$ iff $U=g(T)$ for some polynomial $g$
7843
Show that order of $a^k$
142534
Proof of $k {n\choose k} = n {n-1 \choose k-1}$ using direct proof