# Sunni

less info
reputation
1617
bio website location age member for 2 years seen Oct 16 '12 at 12:42 profile views 379

# 335 Actions

 Apr19 comment An algebra of nilpotent linear transformations is triangularizable@Manos: Yes, it is. Apr19 asked An algebra of nilpotent linear transformations is triangularizable Apr12 comment Prove inequality with norms and matricesIt is homework, so I cannot tell more. My answer does not deserve one vote up? Apr11 revised Prove inequality with norms and matricesadded 203 characters in body Apr11 answered Prove inequality with norms and matrices Apr11 comment Pseudo inner product questionYeah, your inner product is really curious, I found this somewhat related article on standard inner product and angles springerlink.com/content/472w17185p0771w0 Apr10 comment Proof of Pinsker's inequality.I find a simpler one from Borwein\& Levis, 2005, page 63. Apr10 accepted Proof of Pinsker's inequality. Apr9 comment Indefinite Integral for $\cos x/(1+x^2)$I guess there is no explicit formula for the indefinite integral. I know and estimate $$\int_{0}^{\pi/2}\frac{\cos x}{1+x^2}\;dx\ge \int_{0}^{\pi/2}\frac{\sin x}{1+x^2}\;dx$$ Apr5 comment If $A\ge0$ and $B\le 0$, are the eigenvalues of $AB$ non-positive?See e.g., page 57 of Fuzhen Zhang, Matrix Theory: Basic Results and Techniques Second Edition Apr4 comment Proof of Pinsker's inequality.Is there a simpler proof? Apr4 comment If $A\ge0$ and $B\le 0$, are the eigenvalues of $AB$ non-positive?For any square matrices $XY$, its spectrum coincides with that of $YX$. You may first assume $X$ is invertible, otherwise use an $\epsilon$ argument. Apr4 answered If $A\ge0$ and $B\le 0$, are the eigenvalues of $AB$ non-positive? Apr4 asked Proof of Pinsker's inequality. Apr3 comment number of invertible 0-1 matricesSorry all... so the conclusion is that my guess in the question is wrong and there is no known formula. Apr3 comment number of invertible 0-1 matricesIt definitely helps. Apr3 comment number of invertible 0-1 matricesthe matrices considered are with entries from real field. Apr3 revised number of invertible 0-1 matricesadded 4 characters in body Apr3 asked number of invertible 0-1 matrices Apr1 comment Different approaches to evaluate this determinantThanks, bgins's solution works also for general lambda matrices....I am looking for other approaches.