\documentclass{article} \usepackage{amssymb} \usepackage{latexsym} \usepackage{epsf} \title{March 2002 Mock Exam} \date{A four hour examination} \author{Hungarian MO Round 3 for non-specialist classes} \begin{document} \maketitle \begin{enumerate} \item The escribed circle to the side $AB$ of $\Delta ABC$ touches the lines $AB$, $AC$ (produced) at $P, Q$ respectively. The escribed circle to the side $BC$ touches the lines $AC, AB$ at $U, X$ respectively. Prove that the intersection of $PQ$ and $UX$ is as far from $AB$ as from $BC$. \item For which natural numbers $n$, if any, is there an $n$-gon containing exactly $n^2 - 30n + 236$ acute angles? \item Let $n > 1$ be a fixed integer. Find $x_1, \ldots, x_n$ real numbers so that $\sum_i x_i = 2(n-1)$, $\sum (x_i-1)^2 = n$ and $x_n$ is maximized subject to these conditions. \end{enumerate} \end{document}