3
Part of 2004 Indonesia MO
Problems(2)
A certain incenter in a certain triangle
Source: Indonesia Mathematics Olympiad 2004 Day 2 Problem 3
10/22/2009
Given triangle with a right angle, show that the diameter of the incenter is a\plus{}b\minus{}c, where a\equal{}BC, b\equal{}CA, and c\equal{}AB.
geometryincenter
Change those signs!
Source: Indonesia Mathematics Olympiad 2004 Day 1 Problem 3
10/22/2009
In how many ways can we change the sign with \plus{} or \minus{}, such that the following equation is true?
1 *2*3*4*5*6*7*8*9*10\equal{}29