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6
2009 Calculus #6: Class of Polynomials
2009 Calculus #6: Class of Polynomials
Source:
June 23, 2012
calculus
algebra
polynomial
function
Problem Statement
Let
p
0
(
x
)
,
p
1
(
x
)
,
p
2
(
x
)
,
…
p_0(x),p_1(x),p_2(x),\ldots
p
0
(
x
)
,
p
1
(
x
)
,
p
2
(
x
)
,
…
be polynomials such that
p
0
(
x
)
=
x
p_0(x)=x
p
0
(
x
)
=
x
and for all positive integers
n
n
n
,
d
d
x
p
n
(
x
)
=
p
n
−
1
(
x
)
\dfrac{d}{dx}p_n(x)=p_{n-1}(x)
d
x
d
p
n
(
x
)
=
p
n
−
1
(
x
)
. Define the function
p
(
x
)
:
[
0
,
∞
)
→
R
p(x):[0,\infty)\to\mathbb{R}
p
(
x
)
:
[
0
,
∞
)
→
R
by
p
(
x
)
=
p
n
(
x
)
p(x)=p_n(x)
p
(
x
)
=
p
n
(
x
)
for all
x
∈
[
n
,
n
+
1
)
x\in [n,n+1)
x
∈
[
n
,
n
+
1
)
. Given that
p
(
x
)
p(x)
p
(
x
)
is continuous on
[
0
,
∞
)
[0,\infty)
[
0
,
∞
)
, compute
∑
n
=
0
∞
p
n
(
2009
)
.
\sum_{n=0}^\infty p_n(2009).
n
=
0
∑
∞
p
n
(
2009
)
.
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