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Poland - First Round
1993 Poland - First Round
2
2
Part of
1993 Poland - First Round
Problems
(1)
Recursive functions with absolute value
Source: Poland Math Olympiad 1993 Round 1 #2
6/3/2023
The sequence of functions
f
0
,
f
1
,
f
2
,
.
.
.
f_0,f_1,f_2,...
f
0
,
f
1
,
f
2
,
...
is given by the conditions:
f
0
(
x
)
=
∣
x
∣
f_0(x) = |x|
f
0
(
x
)
=
∣
x
∣
for all
x
∈
R
x \in R
x
∈
R
f
n
+
1
(
x
)
=
∣
f
n
(
x
)
−
2
∣
f_{n+1}(x) = |f_n(x)-2|
f
n
+
1
(
x
)
=
∣
f
n
(
x
)
−
2∣
for
n
=
0
,
1
,
2
,
.
.
.
n=0,1,2,...
n
=
0
,
1
,
2
,
...
and all
x
∈
R
x \in R
x
∈
R
. For each positive integer
n
n
n
, solve the equation
f
n
(
x
)
=
1
f_n(x)=1
f
n
(
x
)
=
1
.
function
absolute value