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339114
bio website thales.doa.fmph.uniba.sk/…
location Bratislava, Slovakia
age 35
visits member for 3 years, 1 month
seen 58 mins ago

57m
revised Show that $e^{t(A+B)} = e^{tA}e^{tB}$ for all $t \in \mathbb{R}$ if, and only if $AB = BA$.
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1h
revised Compact and bounded if and only if $X$ is finite dimensional
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4h
comment Is $\int_x^{\infty}e^{-\frac{t^2}{2}} < \frac{1}{x}e^{-\frac{x^2}{2}}$?
A related question: math.stackexchange.com/questions/611724/…
4h
revised Is $\int_x^{\infty}e^{-\frac{t^2}{2}} < \frac{1}{x}e^{-\frac{x^2}{2}}$?
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4h
revised Is $\sum_{k=1}^{n} k^k / \sum_{k=1}^{n} k \in \mathbb{N}$ for some $n > 1$?
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5h
revised First usage of the symbol ∈
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5h
revised Why ${(a^2)}^{\frac 12}=\sqrt {a^2}=|a| \neq a$?
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5h
revised Let n be an integer greater than 3. Find a formula for gcd(n, n + 3)
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5h
revised Let n be an integer greater than 3. Find a formula for gcd(n, n + 3)
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5h
revised How do I prove that an order of a cycle is its length?
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6h
revised A function which is R-integrable but does not have an antiderivative
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6h
revised Calculus question about the existence of antiderivative
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8h
revised Proof by contradiction problem on rational numbers
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8h
comment Apostol - Analytic Number Theory, Chapter 3 problem 4a
Another question about the same identity: math.stackexchange.com/questions/37863/…
8h
revised Apostol - Analytic Number Theory, Chapter 3 problem 4a
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9h
revised Good, satisfied and bad numbers
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9h
revised Prove this identity: $\sin^4x = \dfrac{1}{8}(3 - 4\cos2x + \cos4x)$.
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10h
comment Limit of $\left(1-\frac{1}{n^2}\right)^n$
See also: math.stackexchange.com/questions/762625/…
10h
comment $\lim_{n\to \infty}\left(1 - \frac {1}{n^2}\right)^n =?$
See math.stackexchange.com/questions/576619/…
10h
revised Values $nx - [nx]$ are distinc for an irrational number
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