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10/16/2007

March 10–March 16, 2009

Problem

Find all real solutions of the equation sqrt(1-x) = 2x^2 - 1 + 2x sqrt(1 - x^2) .

Solution

here

List of solvers

Jizhou Li (Michigan Tech undergrad), Dustin Moody (UW grad), Wen Han Wang (UW grad), Koopa Koo (UW grad), Justin Shih (UCLA grad), Gary Raymond (staff); Hai Bin Chang, Lloyd Sakazaki, Peiyush Jain, Adam Welly, Xu Yang, Luan Nguyen (outside).

Trey Sakazaki (6th grade) and Mike Goodman (outside) also gave numerical approximations.

Jizhou Li wins the prize!