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May
19
awarded  Nice Answer
May
19
answered Let A be a $2 \times 2$ matrix with trace $-1$ and determinant $-72$ Find the eigenvalues of $A$
May
19
comment Interior of difference of two convex sets
What part of it don't you understand?
May
19
comment Solve linear system; Gaussian vs. Gauss-Jordan elimination? Solutions?
The rows of all zeros can be ignored.
May
19
comment Solve linear system; Gaussian vs. Gauss-Jordan elimination? Solutions?
Actually that's Gauss-Jordan. In Gaussian elimination you just need zeros below and to the left of the pivot entries.
May
19
answered Interior of difference of two convex sets
May
19
answered Proving the existence of multiple maxima
May
19
answered Is it convex function?
May
19
answered If $A\subset B$, then $\text{ri}\, A\subset\text{ri}\,B$?
May
19
comment Intersection points of curves in MATLAB
The mathematics question is "what is the intersection of two line segments, given coordinates of their endpoints?" Unfortunately you asked a question about Matlab instead.
May
19
accepted Integer solutions of $x^3 = 7y^3 + 6 y^2+2 y$?
May
19
revised Can $\sin(\pi/25)$ be expressed in radicals
added 639 characters in body
May
19
answered Can $\sin(\pi/25)$ be expressed in radicals
May
19
answered Can the matrix expression $D-A^{-1}DA$ be simplified (for diagonal $D$ and symmetric $A$)?
May
18
answered Find the first Poulet number
May
18
comment In Bayesian Statistic how do you usually find out what is the distribution of the unknown?
The choice of the prior distribution $p(\theta)$ is one of the main sources of controversy in Bayesian statistics.
May
18
answered A relation between the domain of $A$ and the domain of $\bar A$
May
18
comment Fourier transform in three dimensions getting out of hand
It doesn't "point" anywhere: it's not a vector, it's a function. Its value at $(0,0,r)$ is the same as its value anywhere else on the sphere $x^2 + y^2 + z^2 = r^2$.
May
18
comment Airy function integral
... but numerically the claimed result doesn't appear to be true. Using Maple I get for the left side approximately $.2671921334-.6269425962 i$ which has absolute value $0.6815046992$, not $1.001$.
May
18
comment Airy function integral
$\text{Ai}$ is an entire function, and $\text{Ai}(z)$ decays rapidly as $|z| \to +\infty$ for any constant argument in the interval $(-\pi/3, \pi/3)$, so you should be able to take any path that goes from $\xi_0$ into a sector $-\pi/3 + \epsilon \le \arg(z) \le \pi/3 - \epsilon$ and then to $\infty$ in that sector, and have the same result for the integral.