Search Me

Recent Posts
 Girls’ Angle Bulletin, Volume 14, Number 1
 Girls’ Angle Bulletin, Volume 13, Number 6
 Thirst For Firsts – A Girls’ Angle Raffle
 Girls’ Angle Bulletin, Volume 13, Number 5
 LCM Optimal Sequences
 Girls’ Angle Bulletin, Volume 13, Number 4
 Girls’ Angle Bulletin, Volume 13, Number 3
 Happy New Year 2020!
 Girls’ Angle Bulletin, Volume 13, Number 2
 Girls’ Angle Bulletin, Volume 13, Number 1
 Why the Girls’ Angle Bulletin?
 Girls’ Angle Bulletin, Volume 12, Number 6
Categories
 applied math (6)
 Contest Math (24)
 gender issues (9)
 math (133)
 Math Education (109)
 Uncategorized (26)
 WIM videos (4)
Archives
 October 2020 (1)
 August 2020 (1)
 July 2020 (1)
 June 2020 (2)
 April 2020 (1)
 February 2020 (1)
 January 2020 (1)
 December 2019 (1)
 October 2019 (2)
 August 2019 (1)
 June 2019 (1)
 May 2019 (1)
 March 2019 (1)
 February 2019 (1)
 January 2019 (1)
 December 2018 (1)
 October 2018 (1)
 September 2018 (1)
 August 2018 (1)
 June 2018 (1)
 April 2018 (1)
 February 2018 (1)
 January 2018 (1)
 December 2017 (1)
 November 2017 (1)
 October 2017 (1)
 August 2017 (1)
 July 2017 (1)
 June 2017 (1)
 April 2017 (2)
 February 2017 (1)
 January 2017 (1)
 December 2016 (2)
 November 2016 (1)
 October 2016 (2)
 September 2016 (1)
 August 2016 (1)
 June 2016 (1)
 April 2016 (1)
 February 2016 (2)
 January 2016 (1)
 December 2015 (1)
 October 2015 (1)
 September 2015 (1)
 August 2015 (2)
 June 2015 (2)
 May 2015 (1)
 April 2015 (1)
 March 2015 (1)
 February 2015 (2)
 January 2015 (1)
 December 2014 (2)
 October 2014 (1)
 September 2014 (1)
 August 2014 (1)
 July 2014 (1)
 June 2014 (2)
 May 2014 (1)
 February 2014 (1)
 January 2014 (4)
 December 2013 (1)
 November 2013 (2)
 September 2013 (2)
 August 2013 (1)
 July 2013 (2)
 June 2013 (1)
 May 2013 (1)
 April 2013 (3)
 March 2013 (1)
 February 2013 (2)
 January 2013 (2)
 December 2012 (2)
 November 2012 (2)
 October 2012 (3)
 September 2012 (8)
 August 2012 (10)
 July 2012 (7)
 June 2012 (3)
 May 2012 (3)
 April 2012 (7)
 March 2012 (4)
 February 2012 (3)
 December 2011 (4)
 November 2011 (7)
 October 2011 (11)
 September 2011 (13)
 August 2011 (16)
Everything Math
 AIME
 angles
 area
 binomial coefficients
 calculus
 Chebyshev polynomials
 chocolate
 circles
 combinatorics
 complex numbers
 conformal
 crossword
 cyclotomic polynomials
 Deanna Needell
 Diophantine equations
 Emily Riehl
 exponentials
 Fermat's little theorem
 Fibonacci
 finite fields
 geometry
 Girls' Angle
 Girls' Angle Bulletin
 Grace Work
 induction
 irreducible polynomials
 Jean Pedersen
 Julia Zimmerman
 Kate Jenkins
 Kristin Lauter
 Laura Pierson
 linear algebra
 lines
 logarithms
 logic
 math
 math contests
 Math Doctor Bob
 math event
 math games
 math magazine
 math prize for girls
 math problems
 math videos
 matrices
 Matthew de CourcyIreland
 minimal polynomials
 multiplication
 optimization
 origami
 parabolas
 Pascal's triangle
 permutations
 perspective drawing
 probability
 puzzle
 Pythagorean theorem
 Pythagorean triples
 raffle contest
 roots
 sets
 similarity
 sine
 stable marriage problem
 sumit
 telescoping sum
 tennis
 tessellations
 tilings
 triangles
 trigonometry
 variables
 volume
 Whitney Souery
 zigzags
Tag Archives: angles
Happy YP Day, HCSSiM!
The yellow pig has a 2 sentence solution!
Posted in Uncategorized
Tagged 17gon, angles, equilateral, geometry, HCSSiM, heptakaidecagon, math problems
Leave a comment
“Parabolas of Apollonius?” Spoiler
This is an answer to the question posed in Parabolas of Apollonius? which was inspired by Maria Monk’s blogpost on the Circles of Apollonius.
Posted in math
Tagged angles, complex function, complex plane, conformal, geometry, parabolas, perpendicular
Leave a comment
Parabolas of Apollonius?
This question is inspired by Maria Monks’ blog post on the Circles of Apollonius. Pictured above are some parabolas from two families of parabolas. The Blue Family is given by the parabolas , for . The Red Family is given … Continue reading
Back to Basics: Arctangent
Recently, a student asked me about problem #8 on the 2008 AIME 1 competition, which is reproduced here for your convenience: Find the positive integer such that . She was able to solve this using the sum of arctangents identity … Continue reading
Stereographic Projection is Conformal
In Hana Kitasei and Tim Reckart’s animated video, Summer Vacation, Angela says that stereographic projection preserves angles. Here’s a proof.