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Today's Calculation Of Integral
2008 Today's Calculation Of Integral
335
335
Part of
2008 Today's Calculation Of Integral
Problems
(1)
Today's calculation of Integral 335
Source: 1994 Hiroshima University entrance exam
6/7/2008
For
t
>
0
t>0
t
>
0
, prove that
1
2
t
∫
t
3
t
x
ln
x
d
x
≥
2
t
ln
2
t
\frac{1}{2t}\int_t^{3t} x\ln x\ dx\geq 2t\ln 2t
2
t
1
∫
t
3
t
x
ln
x
d
x
≥
2
t
ln
2
t
.
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