Difference between revisions of "2023 RMO"

(Created page with "==Problem 1== Let <math>\mathbb{N}</math> be the set of all positive integers and <math>S = {(a,b,c,d) \in \mathbb{N}^{4} : a^{2} + b^{2} + c^{2} = d^{2}}</math>. Find the...")
 
(Problem 6)
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==Problem 6==
 
==Problem 6==
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Consider a set of <math>16</math> points arranged in a <math>4\times4</math> square grid formation. Prove that if any <math>7</math> of these points are coloured blue, then there exists an isosceles right-angled triangle whose vertices are all blue.

Revision as of 07:51, 2 November 2024

Problem 1

Let $\mathbb{N}$ be the set of all positive integers and $S = {(a,b,c,d)  \in  \mathbb{N}^{4} : a^{2} + b^{2} + c^{2} = d^{2}}$. Find the largest positive integer $m$ such that $m$ divides $abcd$ for all $(a,b,c,d)  \in S$.

Problem 2

Problem 3

Problem 4

Problem 5

Problem 6

Consider a set of $16$ points arranged in a $4\times4$ square grid formation. Prove that if any $7$ of these points are coloured blue, then there exists an isosceles right-angled triangle whose vertices are all blue.