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Today's Calculation Of Integral
2008 Today's Calculation Of Integral
375
Today's calculation of Integral 375
Today's calculation of Integral 375
Source:
October 6, 2008
calculus
integration
trigonometry
induction
inequalities
calculus computations
Problem Statement
Prove the following inequality.
1
n
<
∫
0
π
2
1
(
1
+
cos
x
)
n
d
x
<
n
+
5
n
(
n
+
1
)
(
n
=
2
,
3
,
⋯
)
\frac {1}{n} < \int_0^{\frac {\pi}{2}} \frac {1}{(1 + \cos x)^n}\ dx < \frac {n + 5}{n(n + 1)}\ (n =2,3,\ \cdots)
n
1
<
∫
0
2
π
(
1
+
c
o
s
x
)
n
1
d
x
<
n
(
n
+
1
)
n
+
5
(
n
=
2
,
3
,
⋯
)
.
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