IMO 1978 Shortlist

IMO 1978 Shortlist — 17 problems. 17 problems.

17 items

IMO 1978 Shortlist

17 problems · Source: IMO Compendium

Problems

# Origin Problem
1 BUL The set M = {1, 2, . . ., 2n} is partitioned into k nonintersecting
2 BUL Two identically oriented equilateral triangles, ABC with center
3 CUB Let n > m \geq1 be natural numbers such that the groups of
4 CZS Let T1 be a triangle having a, b, c as lengths of its sides and let
5 GDR For every integer d \geq1, let Md be the set of all positive
6 FRA Let ϕ : {1, 2, 3, . . .} … be injective. Prove that
7 FRA We consider three distinct half-lines Ox, Oy, Oz in a plane.
8 GBR Let S be the set of all the odd positive integers that are not
9 GBR Let {f(n)} be a strictly increasing sequence of positive
10 NET An international society has its members in 6 different
11 SWE A function f : I \toR, defined on an interval I, is called
12 USA In a triangle ABC we have AB = AC. A circle is tangent
13 USA Given any point P in the interior of a sphere with ra-
14 VIE Prove that it is possible to place 2n(2n + 1) parallelepipedic
15 YUG Let p be a prime and A = {a1, . . . , ap−1} an arbitrary subset
16 YUG Determine all the triples (a, b, c) of positive real numbers such
17 FRA Prove that for any positive integers x, y, z with xy−z2 = 1 one