Consider an \(n\) by \(n\) chessboard with white/black squares alternating on every row and every column. In how many ways can one choose \(k\) white squares and \(n-k\) black squares from this chessboard with no two squares in a row or column.
Show that for any triangle T and any Jordan curve C in the Euclidean plane, there exists a triangle inscribed in C which is similar to T.
The best solution was submitted by 강한필 (전산학부 2016학번, +4). Congratulations!
Here is his solution of problem 2021-02.
Other solutions was submitted by 하석민 (수리과학과 2017학번, +3), 박은아 (수리과학과 2015학번, +2).