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doraemonpaul
  • Member for 10 years, 1 month
  • Last seen more than 1 year ago
9 votes
1 answer
574 views

$\mathcal{B}^{-1}_{s\to x}\{e^{as^2+bs}\}$ and $\mathcal{L}^{-1}_{s\to x}\{e^{as^2+bs}\}$ , where $a\neq0$

8 votes
3 answers
3k views

How to find the general solution of $xy''-(2x+1)y'+x^2y=0$ when we know the general solution of $y''+2y'+xy=0$?

8 votes
1 answer
364 views

About the great result of $\int\underbrace{x^{x^{\cdot^{\cdot^x}}}}_m~dx$

6 votes
2 answers
589 views

Why solving $\dfrac{\partial u}{\partial x}=\dfrac{\partial^2u}{\partial y^2}$ like this is wrong?

5 votes
1 answer
241 views

About differentiation under the product integral sign

5 votes
1 answer
485 views

About fractional differentiation under the integral sign

5 votes
0 answers
341 views

How to solve the nonlinear higher-order PDEs with overdetermined quantities of conditions whose their most-general solutions are known?

5 votes
1 answer
902 views

About finding the general solution of first-order totally nonlinear PDE with two independent variables

4 votes
1 answer
1k views

Is it possible for cosine functions to have Fourier sine series expressions or sine functions to have Fourier cosine series expressions?

3 votes
0 answers
59 views

About the second-order linear ODEs with polynomial coefficients

3 votes
0 answers
107 views

fancy about some properties of kernel functions at infinity

3 votes
3 answers
394 views

Longest cylinder of specified radius in a given cuboid

3 votes
1 answer
2k views

Does solve PDE by combination of variables always cannot find the general solutions?

2 votes
3 answers
159 views

Iterations of $f(x)=\dfrac{ax+b}{cx+d}$

2 votes
1 answer
660 views

fancy about inverse discrete Fourier sine and cosine transform (i.e. Fourier sine and cosine series)

2 votes
1 answer
122 views

Properties about the Generalized Legendre-type polynomial sequence $f_n(x)=\frac{d^n}{dx^n}(p(x)^n)$

2 votes
1 answer
439 views

about discrete versions of "inverse laplace transform"

2 votes
0 answers
166 views

How to solve the PDEs with more than two independent variables whose their most-general solutions are known?

2 votes
0 answers
803 views

About the inverse laplace transform of sinc function

1 vote
0 answers
73 views

Are there the resources mentioned about finding the general solutions of some first order fully nonlinear PDE examples by method of characteristics?

1 vote
0 answers
102 views

How are the general skills for complete factorization of arbitrary homogeneous order polynomials in $\mathbb{C}$?

1 vote
0 answers
71 views

How the change of variables of a PDE affects the given condition(s)?

1 vote
0 answers
84 views

Properties about the Generalized Hermite-type polynomial sequence $f_n(x)=e^{-p(x)}\frac{d^n}{dx^n}e^{p(x)}$

1 vote
1 answer
390 views

Advanced improper integral involving periodic function of polynomial

1 vote
1 answer
107 views

How to prove the periodicity of an iterated function?

1 vote
1 answer
507 views

How to compute the convolution of two functions which diverge at infinity?

1 vote
0 answers
46 views

About the linear PDE $u_{x_1x_2x_3......x_n}=u$

0 votes
2 answers
140 views

alternative form of the general solution of $u_{xx}+u_{yy}=0$

0 votes
1 answer
181 views

How to determinate the linearly independence between some special functions defined by ODE?

0 votes
2 answers
211 views

properties about number of solutions of transcendental equations