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Beamer
  • Member for 9 years, 9 months
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12 votes
3 answers
4k views

An example of non-closed subspace of a Hilbert space?

7 votes
2 answers
2k views

Completeness of solutions and the separation of variables method

6 votes
0 answers
106 views

a geometric problem about area [duplicate]

5 votes
2 answers
65 views

How to prove this simple fact without using distribution theory?

5 votes
1 answer
265 views

Why only densely defined operators can have an adjoint operator?

5 votes
1 answer
766 views

How to numerically compute the eigenvalues of the Laplacian in a triangular domain with Dirichlet boundary condition?

5 votes
1 answer
269 views

Any article expounding the difference between matrix analysis and functional analysis?

4 votes
1 answer
70 views

Summing up the series $\sum_{n=0}^\infty C_{2n}^n r^{2n} $

3 votes
1 answer
53 views

problem with the ode $f' = a \delta (x) f$

2 votes
0 answers
60 views

Differentiability of the function defined by $\sum_{n\geq 1 } \sin n^2 x / n^{5/2} $

2 votes
2 answers
112 views

Asymptotics of $\sum_{n\geq 1 } \frac{\sin n^2 t }{ n^2 } $

2 votes
1 answer
1k views

Laurent expansion of the gamma function at negative integers

2 votes
2 answers
93 views

What is the simplest way to understand $\nabla \cdot (\nabla \times \textbf{A} ) =0$?

2 votes
0 answers
205 views

kernel space of linear combination of matrices

2 votes
1 answer
163 views

Any elementary derivation of the Pfaff integrability condition?

2 votes
1 answer
49 views

Why is this distribution Poissonian?

2 votes
0 answers
114 views

What is the symmetry of the Penrose tiling?

2 votes
2 answers
1k views

Any example of non-closed operator?

2 votes
1 answer
136 views

zeros of a multi-valued function

2 votes
1 answer
882 views

Why is the Mobius transform called a linear transform? [duplicate]

2 votes
2 answers
173 views

Relations similar to $\sin(\pi/18) + \sin(5\pi/18) = \sin(7\pi/18)$

2 votes
2 answers
127 views

Why $L_X \circ d = d \circ L_X$?

2 votes
0 answers
192 views

Irreducible invariant tensor spaces of the general linear group $GL_n(\mathbb{C})$

2 votes
1 answer
399 views

Simultaneous Diophantine approximation: multiple solutions required

1 vote
1 answer
322 views

How many zeroes does this transcendental equation have?

1 vote
1 answer
47 views

extrapolation to $\infty $ without knowing the exponent

1 vote
0 answers
142 views

Asymptotic value of a summation

1 vote
0 answers
35 views

How to numerically solve an integral equation with a Cauchy principle kernel?

1 vote
1 answer
78 views

About the von Neumann decomposition

1 vote
2 answers
61 views

A question about the form of the Fredholm theorem