Alexander Bogomolny
@CutTheKnotMath
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Freelance mathematician and educational web developer. I am a proud Israeli American, with love and respect for both countries.
NJ, USA
Joined December 2009
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Lorian Saceanu's Inequality for All Triangles https://t.co/hpnqx3PJac
#FigureThat #math #geometry #inequality
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Here's a couple of solutions https://t.co/yAAFspFiwR
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Seeking problems with 4/7 probability being involved. E.g., Diminishing Hopes II #FigureThat #math #probability
https://t.co/Sx6j9Q2dB0
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Every one can take part in this statistical research. Every one is invited
You won't believe what great sh*t a psychologist managed to plant on a predatory journal. https://t.co/i6kCxCeIm7 h/t @maltoesermalte
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Let {x_k} be uniformly distributed on say, [-1,1] with the mean=0. Is that true that the variance is at least the square of the median? #FigureThat #math #probability
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I was always suspicious of the "pseudo" part in pseudorandom
Russians engineer a way to beat slot machines — for which the casinos have no defense. Insanely interesting piece here by @brendankoerner: https://t.co/lGburPSpGX
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Very elegant
Simple way to determine if a year is a leap year: If the last two digits of the year are 00, throw them away and keep only the first two digits. Otherwise, keep only the last two digits. The year is a leap year if what you kept is divisible by 4.
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Oh! It's #ff! Add to this ... @republicofmath (of course!) @cbrownLmath @henryseg @margaretwerth @EulersNephew @maanow @timchartier @evelynjlamb @Dr_Kreisberg @NaturalMath @mikeandallie @MathWithMatthew @DavidKButlerUoA @alittlestats @nomad_penguin @aperiodical @NoCOMTC
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I've nothing to say about that. Perhaps somebody will
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@CutTheKnotMath @yongmaylingjen1 It can be equivalently rephrased as saying that if a product of 2n integers is (-1)^n (n!)^2, then their sum is zero.
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The discriminant of a quadratic polynomial with integer coefficients equals 23. What can be said about the roots of the polynomial. The more you say, the better. #FigureThat #math #algebra
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