Question

Let $A$ be an $n \times n$ matrix with real entries such that $A^2 + I = 0$ then $n$ is even. Not duplicated

score 693 · Answer 1 · 2026-02-23 04:24:34

693

Views

Let $A$ be an $n \times n$ matrix with real entries such that $A^2 + I = 0$ then $n$ is even. Not duplicated

Published on 23 Feb 2026 - 4:24

score 168 · Answer 2 · 2026-02-23 04:19:04

168

Views

Question about a line of reasoning with cyclic subspaces

Published on 23 Feb 2026 - 4:19

score 55 · Answer 3 · 2026-02-23 04:22:28

55

Views

How many $g \in S_6$ are there such that $gxg^{-1} =x?$

Published on 23 Feb 2026 - 4:22

score 29 · Answer 4 · 2026-03-27 15:21:34

29

Views

How many of the following permutations are even?

Published on 27 Mar 2026 - 15:21

score 1.7k · Answer 5 · 2026-04-08 16:50:58

1.7k

Views

Writing permutations as products of adjacent transposition.

Published on 08 Apr 2026 - 16:50

score 133 · Answer 6 · 2026-02-23 04:16:44

133

Views

Why is a hamming (7,4) coding scheme symmetric?

Published on 23 Feb 2026 - 4:16

score 22 · Answer 7 · 2026-02-23 04:20:35

22

Views

Decompose ${\mathbb{Z}_n}^{} / ({\mathbb{Z}_n}^{})^2$ into a direct sum of cyclic groups.

Published on 23 Feb 2026 - 4:20

score 92 · Answer 8 · 2026-02-23 04:19:04

92

Views

Can every finitely generated module be written as a sum of simple modules?

Published on 23 Feb 2026 - 4:19

score 141 · Answer 9 · 2026-02-23 04:22:29

141

Views

Prove $\sum \sqrt{{\frac {2{a}^{2}b}{a+c}}} \leqq a+b+c$ for $a,b,c>0$

Published on 23 Feb 2026 - 4:22

score 57 · Answer 10 · 2026-02-23 04:21:07

57

Views

Prove $\sum \sqrt{3a+\frac{1}{b}} \geq 6$

Published on 23 Feb 2026 - 4:21

score 106 · Answer 11 · 2026-02-23 04:24:34

106

Views

Prove $2\left(x^2+y^2+z^2+1)(x^3y+y^3z+z^3x+xyz\right) \le \left(x^2+y^2+z^2+3xyz\right)^2.$

Published on 23 Feb 2026 - 4:24

score 99 · Answer 12 · 2026-02-23 04:22:02

99

Views

Proving a non-homogeneous inequality with $x,y,z>0$

Published on 23 Feb 2026 - 4:22

score 12.5k · Answer 13 · 2026-02-23 04:24:13

12.5k

Views

Let $A$ be an $n \times n$ matrix with real entries such that $A^2 + I = 0$ then $n$ is even.

Published on 23 Feb 2026 - 4:24

score 244 · Answer 14 · 2026-02-23 04:23:17

244

Views

If the only sub-spaces invariant under $Τ$ are $R^n$ and the zero subspace, then $U$ is diagonalizable.

Published on 23 Feb 2026 - 4:23

score 65 · Answer 15 · 2026-02-23 04:20:36

65

Views

Theorem 3 Corollary 2, Section 7.2 of Hoffman’s Linear Algebra

Published on 23 Feb 2026 - 4:20

List Question

Let $A$ be an $n \times n$ matrix with real entries such that $A^2 + I = 0$ then $n$ is even. Not duplicated

Question about a line of reasoning with cyclic subspaces

How many $g \in S_6$ are there such that $gxg^{-1} =x?$

How many of the following permutations are even?

Writing permutations as products of adjacent transposition.

Why is a hamming (7,4) coding scheme symmetric?

Decompose ${\mathbb{Z}_n}^{} / ({\mathbb{Z}_n}^{})^2$ into a direct sum of cyclic groups.

Can every finitely generated module be written as a sum of simple modules?

Prove $\sum \sqrt{{\frac {2{a}^{2}b}{a+c}}} \leqq a+b+c$ for $a,b,c>0$

Prove $\sum \sqrt{3a+\frac{1}{b}} \geq 6$

Prove $2\left(x^2+y^2+z^2+1)(x^3y+y^3z+z^3x+xyz\right) \le \left(x^2+y^2+z^2+3xyz\right)^2.$

Proving a non-homogeneous inequality with $x,y,z>0$

Let $A$ be an $n \times n$ matrix with real entries such that $A^2 + I = 0$ then $n$ is even.

If the only sub-spaces invariant under $Τ$ are $R^n$ and the zero subspace, then $U$ is diagonalizable.

Theorem 3 Corollary 2, Section 7.2 of Hoffman’s Linear Algebra

Trending Questions

Popular # Hahtags

Popular Questions