1
Part of 2008 ITAMO
Problems(2)
Italian Mathematical Olympiad 2008
Source: Problem 1
8/23/2008
Let be a regular dodecagon, let be the intersection point of the diagonals and . Let be the circle which passes through and , and which has the same radius of the circumcircle of the dodecagon, but is different from the circumcircle of the dodecagon. Prove that:
1. lies on
2. the center of lies on the diagonal
3. the length of equals the length of the side of the dodecagon
geometrycircumcirclegeometry proposed
Italian Mathematical Olympiad 2008
Source: Problem 4
8/23/2008
Find all triples of positive integers such that a^2\plus{}2^{b\plus{}1}\equal{}3^c.
number theory proposednumber theory