### Alexander Bogomolny

Shared publicly -Parametrized quadratic equation with integer solutions http://www.cut-the-knot.org/arithmetic/algebra/UnusualQuadraticEquation.shtml …

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Alexander Bogomolny

Works at CTK Software

Attended Moscow State University

Lives in NJ, USA

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Parametrized quadratic equation with integer solutions http://www.cut-the-knot.org/arithmetic/algebra/UnusualQuadraticEquation.shtml …

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Constructing a regular hexagon from an arbitrary triangle http://www.cut-the-knot.org/m/Geometry/RegularHexagonFromTriangle.shtml

An affine-regular hexagon is constructed starting with an arbitrary triangle. The hexagon then transformed into regular via Napoleon-Barlotti Theorem

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In acute triangles,

a+b+c >= sqrt(2bc.cos(A))+sqrt(2ac.cos(B))+sqrt(2ab.cos(C))

http://www.cut-the-knot.org/arithmetic/algebra/InequalityInAcuteTriangle.shtml

a+b+c >= sqrt(2bc.cos(A))+sqrt(2ac.cos(B))+sqrt(2ab.cos(C))

http://www.cut-the-knot.org/arithmetic/algebra/InequalityInAcuteTriangle.shtml

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A novel identity for two perspective triangles sharing the circumcircle http://www.cut-the-knot.org/pythagoras/VanKhea5.shtml

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An approaching great egret is being watched by a common myna that appears wary of the big bird

#birdphotography #naturephotography

#birdphotography #naturephotography

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For the inradii of the 6 Δs cut of by the altitudes, r1.r3.r5 = r2.r4.r6

http://www.cut-the-knot.org/triangle/InradiiByOrthocenter.shtml

http://www.cut-the-knot.org/triangle/InradiiByOrthocenter.shtml

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In his circles

132 people

Another inequality for integer sequences - in anticipation of a more general one

http://www.cut-the-knot.org/arithmetic/algebra/InequalityForIntegerSequences2.shtml …

http://www.cut-the-knot.org/arithmetic/algebra/InequalityForIntegerSequences2.shtml …

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An inequality for integer sequences

http://www.cut-the-knot.org/arithmetic/algebra/InequalityForIntegerSequences.shtml …

http://www.cut-the-knot.org/arithmetic/algebra/InequalityForIntegerSequences.shtml …

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Monk parakeets. What a convenience to have a supple neck ...

#birdphotography #naturephotography #urbanphotography

#birdphotography #naturephotography #urbanphotography

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A black-crowned night heron that does not appear happy with my intrusion. The Yehoshua Gardens, Tel-Aviv, Israel.

#birdphotography #naturephotography

#birdphotography #naturephotography

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The wall is dirty and the birds are blurred but I have a feeling that the picture may appeal to the catholics among us. The right bird looks to me like a miniature angel stature attached to the wall, the left one appears to be supplicating

#birdphotography #naturephotography #urbanphotography

#birdphotography #naturephotography #urbanphotography

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People

In his circles

132 people

Communities

12 communities

Education

- Moscow State UniversityMS Mathematics, 1966 - 1971
- Hebrew University of JerusalemPhD Mathematics, 1976 - 1981

Basic Information

Gender

Male

Story

Tagline

Love math. Care for math education.

Work

Occupation

Software and web dvelopment, most happily math related

Skills

Mathematics - applied and otherwise, programming Java and C++

Employment

- CTK SoftwarePrincipal, present

Places

Currently

NJ, USA

Links

YouTube

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