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SEEMOUS
2014 SEEMOUS
Problem 4
Problem 4
Part of
2014 SEEMOUS
Problems
(1)
limit integral
Source: SEEMOUS 2014 P4
6/4/2021
a) Prove that
lim
n
→
∞
n
∫
0
n
arctan
x
n
x
(
x
2
+
1
)
d
x
=
π
2
\lim_{n\to\infty}n\int^n_0\frac{\operatorname{arctan}\frac xn}{x(x^2+1)}dx=\frac\pi2
lim
n
→
∞
n
∫
0
n
x
(
x
2
+
1
)
arctan
n
x
d
x
=
2
π
. b) Find the limit
lim
n
→
∞
n
(
m
∫
0
n
arctan
x
n
x
(
x
2
+
1
)
d
x
−
π
2
)
\lim_{n\to\infty}n\left(m\int^n_0\frac{\operatorname{arctan}\frac xn}{x(x^2+1)}dx-\frac\pi2\right)
lim
n
→
∞
n
(
m
∫
0
n
x
(
x
2
+
1
)
arctan
n
x
d
x
−
2
π
)
.
integration
limits
calculus