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johnnycrab
  • Member for 9 years, 6 months
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23 votes
Accepted

RQ decomposition

7 votes
Accepted

Show $\begin{pmatrix} 5 & 1 \\ -6 & 0 \end{pmatrix}$ and $\begin{pmatrix} 7 & -5 \\ 4 & -2 \end{pmatrix}$ are similar.

5 votes
Accepted

Computing the derivative of a matrix-vector dot product

4 votes
Accepted

Tensor product that is not $0$

4 votes
Accepted

Proof that $[\Bbb{Q}(\sqrt{q_1},\dots,\sqrt{q_r}):\Bbb{Q}]=2^r$

3 votes
Accepted

Bus and truck traveling problem

3 votes

Computing normal closure and Galois group of quintic $x^5 - 3$

3 votes

Finding Galois Group

3 votes

Pointwise convergence and uniform convergence converge to same limit?

3 votes
Accepted

Degree of splitting field?

2 votes
Accepted

Is transition matrix between two orthonormal bases orthogonal?

2 votes

How to prove that $\frac{1000!}{(500!)^2}$ is not divisible by 7?

2 votes
Accepted

Conductor of a subring

2 votes
Accepted

Kapranov's Theorem for tropical hypersurfaces: Understanding closure

2 votes
Accepted

Probability : sick people calling doctors

2 votes
Accepted

Source of chapter

2 votes
Accepted

Minimal Galois extension, describe structure of $Gal(L/\mathbb Q)$

2 votes
Accepted

Converting intuition into mathematics (real analysis).

2 votes
Accepted

How do I compute the area of this parallelogram

2 votes
Accepted

Union of closed intervals

2 votes
Accepted

Prove that if $\mu$ is $\sigma$-subadditive then $\mu$ is a measure.

2 votes

Show that group with precisely two subgroups must have prime order

2 votes
Accepted

Does the concept of submultiplicative norm make sense for non-square matrix?

2 votes
Accepted

Show that Ax = b is solvable when [A b] is singular.

2 votes

Complex singularities of $f$ - Radius of convergence

2 votes
Accepted

Showing Lagrange polynomials form a basis for $\Pi_3$.

1 vote
Accepted

Find $M_{B'}^B(id)$.

1 vote
Accepted

If $f$ is continuous, then $(f_n)_n$ converges pointwise to $f$

1 vote

iS It a Complete metric space

1 vote

Questions on factor analysis and linear algebra