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Today's Calculation Of Integral
2007 Today's Calculation Of Integral
168
Today's calculation of Integral 168
Today's calculation of Integral 168
Source: Nagasaki university entrance exam 1980
January 15, 2007
calculus
integration
trigonometry
calculus computations
Problem Statement
Prove that
∑
n
=
1
∞
∫
1
n
+
1
1
n
∣
1
x
sin
π
x
∣
d
x
\sum_{n=1}^{\infty}\int_{\frac{1}{n+1}}^{\frac{1}{n}}{\left|\frac{1}{x}\sin \frac{\pi}{x}\right| dx}
∑
n
=
1
∞
∫
n
+
1
1
n
1
x
1
sin
x
π
d
x
diverge for
x
>
0.
x>0.
x
>
0.
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