- Irrationality Of E 17/10/2010 01:00
Prove that e is irrational.

Problem ID: 377 (17 Oct 2010) / Difficulty: 4 star - Rectangle Construction 17/10/2010 01:00
Find the connection between the constructed length and the original rectangle.

Problem ID: 376 (17 Oct 2010) / Difficulty: 2 star - Inscribed Circle In Isosceles Triangle 16/08/2010 01:00
Find the radius of the circle inscribed inside the isosceles triangle.

Problem ID: 375 (16 Aug 2010) / Difficulty: 2 star - Multiplying Magic Square 16/08/2010 01:00
Show how the values 1, 2, 4, 8, 16, 32, 64, 128, and 256 can be placed in a 3x3 square grid so that the product of each row, column, and diagonal gives the same value.

Problem ID: 374 (16 Aug 2010) / Difficulty: 3 star - Polynomial Roots 07/08/2010 01:00
Prove that the roots of the polynomial, x

Problem ID: 373 (07 Aug 2010) / Difficulty: 3 star^{n}+ c_{n-1}x^{n-1}+ ... + c_{2}x^{2}+ c_{1}x + c_{0}= 0, are irrational or integer. - Hops And Slides But Never Square 07/08/2010 01:00
Prove that the minimum number of moves to completely reverse the positions of the coloured counters can never be square.

Problem ID: 372 (07 Aug 2010) / Difficulty: 3 star - Irrationality Of Pi 24/12/2009
Prove that π is irrational.

Problem ID: 371 (24 Dec 2009) / Difficulty: 4 star - Square And Round Plugs 24/12/2009
Which fits better... a round plug in a square hole or a square plug in a round hole?

Problem ID: 370 (24 Dec 2009) / Difficulty: 2 star - Algebraic Cosine 30/11/2009
Prove that cos(x) is algebraic if x is a rational multiple of Pi.

Problem ID: 369 (30 Nov 2009) / Difficulty: 4 star - Inscribed Square 30/11/2009
Find the side length of the square inscribed inside the right angled triangle.

Problem ID: 368 (30 Nov 2009) / Difficulty: 2 star - Infinite Circles 15/11/2009
What fraction of the large red circle do the infinite set of smaller circles represent?

Problem ID: 367 (15 Nov 2009) / Difficulty: 4 star

- Can You Find... Trigonometric Edition Part 2 01/06/2015 00:00Can you find trig graphs to satisfy a variety of conditions?
- Which Quadratic? 01/09/2014 00:00In this activity you will need to work in a group to connect different representations of quadratics.
- Two-way Functions 01/11/2014 00:00This gives you an opportunity to explore roots and asymptotes of functions, both by identifying properties that functions have in common and also by trying to find functions that have particular properties. You may like to use the list of functions in the Hint, which includes enough functions to complete the table plus some extras.You might like to work on this problem in a pair or small group, or to compare your table to someone else's to see where you have used the same functions and where not.
- Picture the Process I 01/11/2014 00:00How does the temperature of a cup of tea behave over time? What is the radius of a spherical balloon as it is inflated? What is the distance fallen by a parachutist after jumping out of a plane? After sketching graphs for these and other real-world processes, you are offered a selection of equations to match to these graphs and processes.
- Nested Surds 01/05/2015 00:00Can you find values that make these surd statements true?
- Can You Find... Cubic Curves 01/06/2015 00:00Can you find equations for cubic curves that have specific features?
- Curvy Cubics 01/06/2015 00:00Use some calculus clues to pin down an equation of a cubic graph.
- Giants Poster 01/09/2014 00:00
- Equation or Identity (2) 01/04/2015 00:00Here are some more triangle equations. Which are always true?
- Factorial Fragments 01/12/2014 00:00Here you have an expression containing logs and factorials! What can you do with it?
- Paired Parabolas 01/12/1999 00:00Some parabolas are related to others. How are their equations and graphs connected?
- Between 01/12/1999 00:00If you know some points on a line, can you work out other points in between?
- Name That Graph 01/12/1999 00:00How can you work out the equation of a parabola just by looking at key features of its graph?
- Which Fraction Is Bigger? 01/12/1999 00:00Given two algebraic fractions, how can you decide when each is bigger?
- Nine Eigen 01/02/2011 00:00Explore how matrices can fix vectors and vector directions.

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- The Errors of Albert 02/09/2015 22:44
- Was Einstein the First to Invent <em>E = mc<sup>2</sup></em>? 24/08/2015 16:00
- How Einstein Discovered General Relativity amid War, Divorce and Rivalry 24/08/2015 14:00
- Everything Looks Better in the Hyperbolic Plane 21/08/2015 13:30
- What Einstein Got Wrong 20/08/2015 15:00
- Book Review: <i>Spurious Correlations</i> 07/08/2015 15:00
- Jon Stewart's Top 10 Science Moments on <i>The Daily Show</i> [Video] 07/08/2015 14:15
- How to Revamp Education for 21st-Century Learners 05/08/2015 23:00
- What Are the Odds of Successfully Navigating an Asteroid Field? 05/08/2015 13:15
- Which Character Strengths Are Most Predictive of Well-Being? 03/08/2015 00:17
- How to Get to the Fourth Dimension 31/07/2015 14:30
- The World's Most Accurate Parquet Floor–Based Personality Test 24/07/2015 17:30
- What It Feels like to Be Cedric Villani 08/07/2015 21:00
- Researchers Race to Rescue the Enormous Theorem before Its Giant Proof Vanishes 08/07/2015 13:30
- Back Algorithmic Knitting on Kickstarter 03/07/2015 15:00
- A Belated Apology to Mozart and Modular Arithmetic 28/06/2015 03:00
- Mathematical Art Takes a Fresh Look at Wallpaper 26/06/2015 13:00
- What Is the Famous Monty Hall Problem? 24/06/2015 14:00
- LEGO Adds More Women in Science to Its Lineup 24/06/2015 12:00
- Restore Research to Preserve the American Dream 23/06/2015 16:54
- 100 Years of Great Physics: Watch Live Monday and Tuesday [Video] 22/06/2015 18:00
- A Few of My Favorite Spaces: Cantor's Leaky Tent 20/06/2015 22:00
- Furor over Tim Hunt Must Lead to Systemic Change 15/06/2015 22:50
- Why Tim Hunt's Sexist Comments Were No "Joke" 15/06/2015 22:45