João Víctor Melo's user avatar
João Víctor Melo's user avatar
João Víctor Melo's user avatar
João Víctor Melo
  • Member for 3 years, 3 months
  • Last seen more than a month ago
  • Brazil
2 votes

Show that $\frac{a_1}{b_1}+\frac{a_2}{b_2}+...+\frac{a_n}{b_n} \geq n$

2 votes

$\lim_{n \rightarrow \infty}\left(1+\dfrac{2}{n}\right)^{n^2}e^{-2n}$

1 vote

The natural sequence {$a_n$} is given. Need to prove that from some point all values of $a_n$ will be the same.

1 vote

How to solve these seemingly overly hard differentiation questions?

1 vote

How do we calculate $\cos (3\pi/4+k\pi)$?

1 vote

$\lim_{n\to\infty} \frac{10^n}{\sqrt{(n+1)!} + \sqrt{n!}}\,.$

1 vote

Differential equation of type $u_{tt}=u_{xx} + u$ with specific boundary conditions

1 vote
Accepted

Prove that $\sum_{n=0}^\infty c_nx^n$ and $\sum_{n=0}^\infty n\log n c_nx^{n+3}$ have same radius of convergence.

1 vote
Accepted

The Radius of Convergence of $\sum_{n=1}^{\infty} x^n\left( \frac{n}{2n+1} \right)^{2n-1}$

1 vote

Rolle theorem for the Number of roots of a real function

1 vote

Peano axioms proof

1 vote

Let A,B be two events such that $P(A|B) > P(B)$, Prove that $P(B^c|A^c)>P(B^c)$

1 vote

What is $ x^{23^{33}}\pmod{77}$

1 vote

Compute $\lim _{x\to 0}\left(\frac{\sqrt[3]{x}}{x}\right)$

1 vote

How to calculate this determinant (Finding characteristic polynomial).

1 vote

Create context-free grammar for $\{w \mid |w| $ is odd with a 0 in the middle$\}$

0 votes

Matrix with integer coordinates

0 votes

Verify the identity: $\tan^{-1} x +\tan^{-1} (1/x) = \pi /2$

0 votes

Determine $p$ for one to have $\displaystyle\frac{1}{5}+\frac{1}{6}=\frac{1+1}{5+6}=\frac{2}{11}$, in $\mathbb{Z_p}$.

0 votes

convergence $\sum_{n=1}^{\infty}\frac{1}{n}\sin\left(\frac{\pi}{n^{2}}\right)$

0 votes

Show that the set of all subsets of an infinite enumerable set is not enumerable

0 votes

Show that the sum of a set of matrices isn't direct, and that the sum is the whole vector space.

0 votes

What makes an integral an integral?

0 votes

Ramanujan and sum of four cubes

0 votes

Derivative of a function using definition at a point

0 votes

Changing order of integration for $\int_{1}^{2}\int_{2-x}^{\sqrt{2x-x^2}}f(x,y)dydx$

0 votes

Sum ${\sum_{n=1}^\infty \frac{4}{n(n+3)}}$

0 votes

Formal Definition of Limit and Proofs

0 votes
Accepted

Interconversion between Complex Number Forms

0 votes

Does the following sequence defined recursively converge?