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2011 IMAR Test
3
3
Part of
2011 IMAR Test
Problems
(1)
exists f:R \to R, f(x)+f(2x)+...+f(nx) = 0 for all x \in R, f(x) = 0 iff x=0
Source: IMAR 2011 p3
9/27/2018
Given an integer number
n
≥
2
n \ge 2
n
≥
2
, show that there exists a function
f
:
R
→
R
f : R \to R
f
:
R
→
R
such that
f
(
x
)
+
f
(
2
x
)
+
.
.
.
+
f
(
n
x
)
=
0
f(x) + f(2x) + ...+ f(nx) = 0
f
(
x
)
+
f
(
2
x
)
+
...
+
f
(
n
x
)
=
0
, for all
x
∈
R
x \in R
x
∈
R
, and
f
(
x
)
=
0
f(x) = 0
f
(
x
)
=
0
if and only if
x
=
0
x = 0
x
=
0
.
function
algebra
functional equation