Difference between revisions of "2016 IMO Problems/Problem 5"

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==Problem==
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The equation
 
The equation
 
<center><math>(x-1)(x-2)\cdots(x-2016)=(x-1)(x-2)\cdots (x-2016)</math></center>
 
<center><math>(x-1)(x-2)\cdots(x-2016)=(x-1)(x-2)\cdots (x-2016)</math></center>
 
is written on the board, with <math>2016</math> linear factors on each side. What is the least possible value of <math>k</math> for which it is possible to erase exactly <math>k</math> of these <math>4032</math> linear factors so that at least one factor remains on each side and the resulting equation has no real solutions?
 
is written on the board, with <math>2016</math> linear factors on each side. What is the least possible value of <math>k</math> for which it is possible to erase exactly <math>k</math> of these <math>4032</math> linear factors so that at least one factor remains on each side and the resulting equation has no real solutions?
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==Solution==
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{{solution}}
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==See Also==
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{{IMO box|year=2016|num-b=4|num-a=6}}

Latest revision as of 00:37, 19 November 2023

Problem

The equation

$(x-1)(x-2)\cdots(x-2016)=(x-1)(x-2)\cdots (x-2016)$

is written on the board, with $2016$ linear factors on each side. What is the least possible value of $k$ for which it is possible to erase exactly $k$ of these $4032$ linear factors so that at least one factor remains on each side and the resulting equation has no real solutions?

Solution

This problem needs a solution. If you have a solution for it, please help us out by adding it.

See Also

2016 IMO (Problems) • Resources
Preceded by
Problem 4
1 2 3 4 5 6 Followed by
Problem 6
All IMO Problems and Solutions