Mélanie De la Cheminée's user avatar
Mélanie De la Cheminée's user avatar
Mélanie De la Cheminée's user avatar
Mélanie De la Cheminée
  • Member for 7 years
  • Last seen more than 5 years ago
6 votes
2 answers
137 views

Calculate this integral $\int_a^b (\int_a^b \frac{f(t) \overline{f(s)}}{1-ts} \,ds) \, dt$

4 votes
3 answers
91 views

Fourier transform of $G_s(x) = \frac{1}{\sqrt{s}} e^{-\frac{\pi x^2}{s}}$

4 votes
4 answers
291 views

Calculate integral $\int_{-1}^{1} (1-x^2)^n dx $ [duplicate]

3 votes
2 answers
533 views

Does this system of equations have any solutions?

3 votes
3 answers
55 views

Why $ (n+1)(1-x)c^n \rightarrow_{n \rightarrow +\infty} 0$

3 votes
2 answers
369 views

Orthographic projection on a closed subspace $E$ of $H$, Hilbert space

2 votes
1 answer
35 views

Norm $L^p$ for the function $f(x) = \sin(e^{x^3}) 1_{A \cap \mathbb{Q}}(x) + e^{-x} 1_{A/\mathbb{Q}}(x)$

2 votes
0 answers
553 views

Holder inequality, Lp and Lq spaces

2 votes
0 answers
396 views

$A$ tridiagonal positive definite matrix, $2D-A$ also?

2 votes
0 answers
62 views

Lebesgue Integrability : for what values of $\alpha$?

2 votes
1 answer
101 views

Prove that $\int_{[a,n]} |f_n| d \lambda = \int |1_{[a,n]} f| d \lambda < +\infty$ for $f$ Riemann locally integrable

2 votes
1 answer
413 views

Limit superior and limit inferior, measure theory

2 votes
2 answers
51 views

Integral of $\frac{\sqrt{|x|}}{1-x} 1_{[0,\alpha]}(x)$ and series with positive terms

2 votes
1 answer
1k views

Differential equation, periodic solution, eigenvalues

2 votes
1 answer
72 views

Markov chains $(Z_n)$, how to find the probability $\mathbb{P} (Z_{n+1} = i+1 \mid Z_n = i)$?

1 vote
0 answers
45 views

Subsets in $\mathbb{Z}^2$, particle, order of magnitude

1 vote
1 answer
229 views

How to prove that the maximal solution of $x'(t) = e^{-g(x(t))^2}$ is global?

1 vote
1 answer
61 views

How to study the ODE $x'(t) = \sqrt{x(t)^2 + 1}$ with $x(0)=a$?

1 vote
2 answers
60 views

Transform an equation of order $2$ ($y''(t) + \mu y'(t) + \sin(y(t)) = 0$) to a system of order $1$

1 vote
0 answers
33 views

Estimation of the law $Z_{1000}/\sqrt{1000}$ with an histogram (+ asymptotic positions)

1 vote
1 answer
40 views

Linear algebra : Why $C_{n+1} - A^{-1} = (C_n - A^{-1})NM^{-1}$ and why $(C_n)$ converges to $A^{-1}$?

1 vote
0 answers
57 views

Spectral radius of $I_d - \dfrac{w}{2} A$, simple calculation, tridiagonal matrix $A$

1 vote
2 answers
94 views

Linearized equation of $x'(t) = f(x(t))$ in the neighbourhood of the equilibrium points found

1 vote
0 answers
56 views

Cauchy's problem, $x'(t) = f(t,x(t))$ with $a < f(t,x(t)) < b$, $f$ is continuous and $C^1$, what are the limits of $x(t)$?

1 vote
1 answer
79 views

How to prove that $\mu(A_q) \leq 2/q^{1+\epsilon}$ with $A_q = [0,1] \bigcap \bigcup_{p=0}^q [p/q-1/q^{2+\epsilon},p/q+1/q^{2+\epsilon}]$?

1 vote
2 answers
72 views

Why a maximal solution $u$ not identically zero admits at most a zero?

1 vote
2 answers
150 views

How to prove that $\mu(\{x\}) = \mu(\{y\}) = 0$ for a measure $\mu$?

1 vote
1 answer
58 views

Calculate $\int_{[0,1/k]} d\mu$ with $\mu$ measure

1 vote
1 answer
205 views

Maximal solution and interval of differential equation $y'=y\ln(1+y)$

1 vote
3 answers
822 views

Why $\mu(\lim \sup(A_n)) = 0$ if $\sum_{n\geq 1} \mu(A_n)<\infty$?