Search Me

Recent Posts
 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
 Girls’ Angle Bulletin, Volume 12, Number 5
Categories
 applied math (5)
 Contest Math (24)
 gender issues (9)
 math (132)
 Math Education (108)
 Uncategorized (26)
 WIM videos (4)
Archives
 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
 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
 vectors
 volume
 Whitney Souery
 zigzags
Category Archives: Contest Math
Conceptual Solution to 2008 AIME I, Problem 14
Here’s a solution to problem 14 on the 2008 AIME I contest that attempts to avoid computation as much as possible. Sometimes, it’s an amusing exercise to try to solve a contest problem entirely in your head. Doing so often forces … Continue reading
Posted in Contest Math, math
Tagged AIME, circles, ellipse, geometry, optimization, tangent
Leave a comment
Do you believe this?
Here’s a triangle: I’ll use the vertex labels to also denote the corresponding angle measures. Take the sines of all 3 angles in the triangle: , , and . Would you believe it if I told you that these three … Continue reading
Posted in Contest Math, math
Tagged law of cosines, Ptolemy's theorem, similarity, sine, triangles, trigonometry
Leave a comment
2013 AIME 2 Problem 10
I’ve been asked about the following problem from the 2013 AIME 2 a few times, so I decided to blog a couple of solutions for it: Given a circle of radius , let A be a point at a distance from … Continue reading
2012 Math Prize for Girls: #1620
Here are comments and solutions to (some of) the problems on the 2012 Math Prize for Girls contest that took place at MIT on September 22.
Use Your Mind to Save Yourself Time
I’m looking forward to Games Night at the Math Prize for Girls coming up this weekend. I’ve been working with the author of “Mess or Math?” to create a really fun math activity and I hope many of you who … Continue reading
Posted in Contest Math, math, Math Education
Tagged AMC 12, circles, circumference, geometry, similarity, tangent circles
Leave a comment
2011 Math Prize for Girls: #15
Here are comments and solutions to problems 15 on the 2011 Math Prize for Girls contest that took place at MIT on September 17, 2011. Earlier I blogged comments and solutions for problems 610, problems 1115, and problems 1620.
2011 Math Prize for Girls: #610
Here are comments and solutions to problems 610 on the 2011 Math Prize for Girls contest that took place at MIT on September 17, 2011. Earlier I blogged comments and solutions for problems 1115 and problems 1620.
2012 AIME 1 Problem #12
I was checking out Mess or Math?’s cool blog and her latest post wonders whether problem 12 on the 2012 AIME 1 has a simple solution. Simple is a subjective term. The problem’s setup certainly suggests invoking things like the … Continue reading
2011 Math Prize for Girls: #1115
Here are comments and solutions to problems 1115 on the 2011 Math Prize for Girls contest that took place at MIT on September 17, 2011. Click here for comments and solutions for problems 15. Click here for comments and solutions for … 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