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10
SMT 2013 Calculus #10
SMT 2013 Calculus #10
Source:
February 3, 2013
calculus
limit
integration
trigonometry
Problem Statement
Evaluate
lim
n
→
∞
[
(
∏
k
=
1
n
2
k
2
k
−
1
)
∫
−
1
∞
(
cos
x
)
2
n
2
x
d
x
]
\lim_{n\to\infty}\left[\left(\prod_{k=1}^{n}\frac{2k}{2k-1}\right)\int_{-1}^{\infty}\frac{(\cos x)^{2n}}{2^x} \, dx\right]
lim
n
→
∞
[
(
∏
k
=
1
n
2
k
−
1
2
k
)
∫
−
1
∞
2
x
(
c
o
s
x
)
2
n
d
x
]
.
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