- 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

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