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KoMaL A Problems
KoMaL A Problems 2018/2019
A. 744
A. 744
Part of
KoMaL A Problems 2018/2019
Problems
(1)
Vectors With Special Properties
Source: KöMaL A. 744
3/19/2022
Show that for every odd integer
N
>
5
N>5
N
>
5
there exist vectors
u
,
v
,
w
\bf u,v,w
u
,
v
,
w
in (three-dimensional) space which are pairwise perpendicular, not parallel with any of the coordinate axes, have integer coordinates, and satisfy
N
=
∣
u
∣
=
∣
v
∣
=
∣
w
∣
.
N\bf =|u|=|v|=|w|.
N
=
∣u∣
=
∣v∣
=
∣w∣.
Based on problem 2 of the 2018 Kürschák contest
komal
geometry
vector