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1995 IMC
3
IMC 1995 Problem 3
IMC 1995 Problem 3
Source: IMC 1995
February 18, 2021
differentiable function
real analysis
Problem Statement
Let
f
f
f
be twice continuously differentiable on
(
0
,
∞
)
(0,\infty)
(
0
,
∞
)
such that
lim
x
→
0
+
f
′
(
x
)
=
−
∞
\lim_{x \to 0^{+}}f'(x)=-\infty
lim
x
→
0
+
f
′
(
x
)
=
−
∞
and
lim
x
→
0
+
f
′
′
(
x
)
=
∞
\lim_{x \to 0^{+}}f''(x)=\infty
lim
x
→
0
+
f
′′
(
x
)
=
∞
. Show that
lim
x
→
0
+
f
(
x
)
f
′
(
x
)
=
0.
\lim_{x\to 0^{+}}\frac{f(x)}{f'(x)}=0.
x
→
0
+
lim
f
′
(
x
)
f
(
x
)
=
0.
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