user avatar
user avatar
user avatar
guestDiego
  • Member for 6 years
  • Last seen more than 5 years ago
34 votes

Rigorous definition of "differential"

16 votes
Accepted

Why don't we see a $\frac{\times}{ \div}$ like we see $\pm$?

15 votes

Hyper Derivative definition.

11 votes

Is it possible to interchange countable unions and intersections?

11 votes
Accepted

Example of a non complete normed vector space.

11 votes

Minimum number of flips to guarantee heads

11 votes
Accepted

How can I find an explicit expression for this recursively defined sequence?

9 votes

Which of the numbers is larger: $7^{94}$ or $9^{91} $?

7 votes
Accepted

Example of a strictly convex function unbounded in $\mathbb{R}$

7 votes
Accepted

Show that $\lim_{n\to\infty} \sqrt[n]{a^{n} + b^{n}} = \max(a, b)$

6 votes

Find two positive real numbers, whose difference is 100 and whose product is a minimum

6 votes
Accepted

How to prove this limit: $\lim_{n\to \infty}n(\sqrt[n]{x}-1)=\ln(x)$?

5 votes

Prove that, at least one of the matrices $A+B$ and $A-B$ has to be singular

5 votes
Accepted

Can the directional derivative fail to be linear?

5 votes

Closed form for $1^k + ... + n^k$ (generalized Harmonic number)

5 votes
Accepted

What is $\lim_{n \to \infty} \frac{x^n-x^{-n}}{x^n+x^{-n}}$ when $0\lt x \lt 1$?

5 votes
Accepted

Deriving $\frac{\partial (ABC)}{\partial B}$

5 votes

Does the perimeter of a polygon necessarily decrease if more edges are added to it, with the constraint of constant area?

5 votes
Accepted

$\mathbb{R}$ is complete $\rightarrow$ $\mathbb{C}$ is complete

5 votes

Convergence of $\sum_{n=1}^{\infty}\left(\sqrt{n^2+1} - \sqrt[3]{n^3+1}\right)$

4 votes

How to calculate a vector that is rotated by 90 when multiplied by a random matrix

4 votes
Accepted

Writing open interval as infinite union of closed intervals

4 votes
Accepted

Characteristic function of Laplace distribution

4 votes

If $A$ is a matrix of size $n\times n$, and $A^2+A+2I=0$

3 votes

Is this Series Convergent and does it also Absolutely Converge?

3 votes
Accepted

Find a bijection between the Reals and an interval

3 votes

Find $\lim_{n \rightarrow \infty} \frac{1}{\sqrt{n}}(1+\frac{1}{\sqrt{2}}+\frac{1}{\sqrt{3}}+....\frac{1}{\sqrt{n}})$

3 votes
Accepted

Are the norms on a vector space unique?

3 votes
Accepted

Fig 1.8 on page 16 of Guillemin and Pollack's "differential topology"

3 votes

Simplifying $\int_{-\infty}^z \phi(x)\,\Phi(\beta\, x)\,dx$, $\phi(x)$ pdf of normal, $\Phi(x)$ CDF of normal

1
2 3 4 5