- 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

- Designing a Polynomial 01/12/1999 00:00Can you find a polynomial function whose first derivative is equal to the function?
- Can You Find... Trigonometry Edition 01/04/2015 00:00What graphs can you make by transforming sine, cosine and tangent graphs?
- Equation or Identity (1) 01/04/2015 00:00Which of these equations concerning the angles of triangles are always true?
- Equation or Identity (2) 01/04/2015 00:00Here are some more triangle equations. Which are always true?
- Have a Sine 01/04/2015 00:00There's much more to trigonometry than sin, cos and tan...
- The Quintessential Proof 01/03/2015 00:00In this resource, the aim is to understand a fundamental proof of Pythagoras's Theorem.
- Finding Circles 01/03/2015 00:00Can you find the centre and equation of a circle given a number of points on the circle? When is it possible and when is it not?
- The Circle of Apollonius... Coordinate Edition 01/03/2015 00:00Can you sketch and then find an equation for the locus of a point based on its distance from two fixed points?
- Nine Eigen 01/02/2011 00:00Explore how matrices can fix vectors and vector directions.
- Absolutely! 01/11/2014 00:00What can you say about this graph? A number of questions have been suggested to help you look at the graph in different ways. Use these to help you make sense of this and similar graphs.
- 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.
- 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.
- Factorial Fragments 01/12/2014 00:00Here you have an expression containing logs and factorials! What can you do with it?
- Giants Poster 01/09/2014 00:00
- Which Quadratic? 01/09/2014 00:00In this activity you will need to work in a group to connect different representations of quadratics.

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- 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
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- When the <i>Mona Lisa</i> Is NP-Hard 31/05/2015 16:30
- A Few of My Favorite Spaces: The Topologist's Sine Curve 28/05/2015 22:00
- John Nash, Mathematician Who Inspired "A Beautiful Mind", Killed in Car Crash 24/05/2015 18:25
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- Moore's Law Keeps Going, Defying Expectations 19/05/2015 22:00
- Grapefruit Math 19/05/2015 13:00
- The Equation for a Happy Mother's Day 06/05/2015 14:00
- Star Wars Day: May the Fourth Be with You 02/05/2015 17:57
- 5 Instagram Tips for Science Artists 29/04/2015 18:30
- The Truth Behind the Math: The Surprising Path of a Theorem [Q&A] 27/04/2015 20:00
- Book Review: Birth of a Theorem 24/04/2015 20:00
- In Praise of Fractals and Poetry 20/04/2015 18:00
- Scientists Perturbed by Loss of Stat Tools to Sift Research Fudge from Fact 16/04/2015 15:30
- Boots or Heels: My Wardrobe Paradox as a Woman in STEM 14/04/2015 14:17
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