IMO 1972 Longlist

IMO 1972 Longlist — 34 problems.

34 items

IMO 1972 Longlist

34 problems · Source: IMO Compendium

Problem Origin Statement
BUL1 BUL Find all integer solutions of the equation
BUL2 BUL Find all real values of the parameter a for which the system of
BUL3 BUL On a line a set of segments is given of total length less than
BUL4 BUL Given a triangle, prove that the points of intersection of three
BUL5 BUL Given a pyramid whose base is an n-gon inscribable in a circle,
BUL6 BUL Prove the inequality
CZS9 CZS Given natural numbers k and n, k \leqn, n \geq3, find the set
CZS10 CZS Given five points in the plane, no three of which are collinear,
CZS12 CZS A circle k = (S, r) is given and a hexagon AA′BB′CC′ inscribed
CZS13 CZS Given a sphere K, determine the set of all points A that are
GBR16 GBR Consider the set S of all the different odd positive integers
GBR17 GBR A solid right circular cylinder with height h and base-radius
GBR18 GBR We have p players participating in a tournament, each player
GBR19 GBR Let S be a subset of the real numbers with the following
MON23 MON Does there exist a 2n-digit number a2na2n−1 . . . a1 (for an
MON24 MON The diagonals of a convex 18-gon are colored in 5 different
NET25 NET We consider n real variables xi (1 \leqi \leqn), where n is an
NET28 NET The lengths of the sides of a rectangle are given to be odd
NET29 NET Let A, B, C be points on the sides B1C1, C1A1, A1B1 of a
ROM31 ROM Find values of n \inN for which the fraction 3n−2
ROM32 ROM If n1, n2, . . . , nk are natural numbers and n1+n2+\cdot \cdot \cdot+nk = n,
ROM33 ROM A rectangle ABCD is given whose sides have lengths 3 and
ROM34 ROM If p is a prime number greater than 2 and a, b, c integers not
ROM35 ROM (a) Prove that for a, b, c, d \inR, m \in[1, +\infty) with am + b =
ROM36 ROM A finite number of parallel segments in the plane are given with
SWE37 SWE On a chessboard (8 \times 8 squares with sides of length 1) two
SWE38 SWE Congruent rectangles with sides m (cm) and n (cm) are
SWE39 SWE How many tangents to the curve y = x3 −3x (y = x3 + px)
SWE40 SWE Prove the inequalities
SWE41 SWE The ternary expansion x = 0.10101010 . . . is given. Give the
SWE42 SWE The decimal number 13101 is given. It is instead written as a
USS43 USS A fixed point A inside a circle is given. Consider all chords
USS45 USS Let ABCD be a convex quadrilateral whose diagonals AC and
USS46 USS Numbers 1, 2, . . . , 16 are written in a 4\times4 square matrix so that