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Putnam
1946 Putnam
A4
A4
Part of
1946 Putnam
Problems
(1)
Putnam 1946 A4
Source: Putnam 1946
3/13/2022
Let
g
(
x
)
g(x)
g
(
x
)
be a function that has a continuous first derivative
g
′
(
x
)
g'(x)
g
′
(
x
)
. Suppose that
g
(
0
)
=
0
g(0)=0
g
(
0
)
=
0
and
∣
g
′
(
x
)
∣
≤
∣
g
(
x
)
∣
|g'(x)| \leq |g(x)|
∣
g
′
(
x
)
∣
≤
∣
g
(
x
)
∣
for all values of
x
.
x.
x
.
Prove that
g
(
x
)
g(x)
g
(
x
)
vanishes identically.
Putnam
function
calculus
derivative