Pedro A's user avatar
Pedro A's user avatar
Pedro A's user avatar
Pedro A
  • Member for 9 years, 4 months
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18 votes
3 answers
8k views

Does swapping columns of a matrix cause the rows of the inverse matrix to be swapped?

14 votes
1 answer
488 views

Is $\cos(\alpha x + \cos(x))$ periodic?

9 votes
1 answer
1k views

Regarding functions from R² to R: continuity and differentiability

8 votes
1 answer
601 views

Continuous functions and uncountable intersections with the x-axis

6 votes
1 answer
103 views

What are the conditions on $f$ for $\sup f$ and $f(\sup)$ be interchangeable?

5 votes
2 answers
454 views

Does the Shannon Entropy always exist (even for infinite distributions)?

5 votes
2 answers
520 views

Line Integrals FT usage on this strange vector field: so what are the exact conditions?

5 votes
3 answers
1k views

If $f$ is continuous and $f(A)$ is open, is $A$ necessarily open?

4 votes
2 answers
835 views

What does it mean for a number to be independent of ZFC?

3 votes
1 answer
46 views

Is this condition necessary for a function $f : \mathbb{R}^m \to \mathbb{R}^n$ to be differentiable?

3 votes
1 answer
5k views

Understanding the definition of ergodicity through examples

3 votes
1 answer
205 views

Is there an alternative definition of uniform differentiability that implies differentiability, instead of requiring it?

2 votes
0 answers
148 views

Is being real analytic at a point equivalent of matching the Taylor Series around that point?

2 votes
2 answers
4k views

Prove that the sum of inverses of factorials is convergent

2 votes
1 answer
98 views

Is there a function with two different pseudo-primitives? (Motivated by FTC)

2 votes
0 answers
49 views

Limit of a ratio of two similar binomial coefficients with two variables

2 votes
1 answer
166 views

"There exists" versus "we can construct": computability and the axiom of choice

1 vote
1 answer
112 views

Is this "Simple Proof of Godel's Theorems" assuming some form of the Axiom of Choice?

1 vote
1 answer
43 views

Amount of nondecreasing integer k-tuples with limited delta

1 vote
0 answers
393 views

Relation between bilinear symplectic forms and symplectic matrices

1 vote
3 answers
902 views

Eigenvalues of matrix $A^TA+I$ are real and greater than 1?

1 vote
1 answer
370 views

If a compact set's boundary is the finite union of smooth Jordan curves, is it a domain?

1 vote
2 answers
44 views

Convergence of this alternating series: $\sum_{k=0}^\infty \frac{(-1)^k}{(k+1)C^k} = C \log \frac{C+1}{C}$

0 votes
2 answers
27 views

Is it always possible to increase the set of LI columns of a matrix if the rank is higher?

0 votes
1 answer
1k views

How to calculate the partial derivative with respect to the complex conjugate in this situation?

0 votes
0 answers
18 views

Does this definition of equality to a class really require a substitution of variables?