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Today's Calculation Of Integral
2007 Today's Calculation Of Integral
225
225
Part of
2007 Today's Calculation Of Integral
Problems
(1)
Today's calculation of Integral 225
Source: Kogakuin University entrance exam 2007
9/16/2007
2 Points
P
(
a
,
1
a
)
,
Q
(
2
a
,
1
2
a
)
(
a
>
0
)
P\left(a,\ \frac{1}{a}\right),\ Q\left(2a,\ \frac{1}{2a}\right)\ (a > 0)
P
(
a
,
a
1
)
,
Q
(
2
a
,
2
a
1
)
(
a
>
0
)
are on the curve C: y \equal{}\frac{1}{x}. Let
l
,
m
l,\ m
l
,
m
be the tangent lines at
P
,
Q
P,\ Q
P
,
Q
respectively. Find the area of the figure surrounded by
l
,
m
l,\ m
l
,
m
and
C
C
C
.
calculus
integration
geometry
logarithms
ratio
inequalities
function