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Taiwan National Olympiad
2002 Taiwan National Olympiad
5
5
Part of
2002 Taiwan National Olympiad
Problems
(1)
vlue of a sum
Source: 11-th Taiwanese Mathematical Olympiad 2002
1/22/2007
Suppose that the real numbers
a
1
,
a
2
,
.
.
.
,
a
2002
a_{1},a_{2},...,a_{2002}
a
1
,
a
2
,
...
,
a
2002
satisfying
a
1
2
+
a
2
3
+
.
.
.
+
a
2002
2003
=
4
3
\frac{a_{1}}{2}+\frac{a_{2}}{3}+...+\frac{a_{2002}}{2003}=\frac{4}{3}
2
a
1
+
3
a
2
+
...
+
2003
a
2002
=
3
4
a
1
3
+
a
2
4
+
.
.
.
+
a
2002
2004
=
4
5
\frac{a_{1}}{3}+\frac{a_{2}}{4}+...+\frac{a_{2002}}{2004}=\frac{4}{5}
3
a
1
+
4
a
2
+
...
+
2004
a
2002
=
5
4
.
.
.
...
...
a
1
2003
+
a
2
2004
+
.
.
.
+
a
2002
4004
=
4
4005
\frac{a_{1}}{2003}+\frac{a_{2}}{2004}+...+\frac{a_{2002}}{4004}=\frac{4}{4005}
2003
a
1
+
2004
a
2
+
...
+
4004
a
2002
=
4005
4
Evaluate the sum
a
1
3
+
a
2
5
+
.
.
.
+
a
2002
4005
\frac{a_{1}}{3}+\frac{a_{2}}{5}+...+\frac{a_{2002}}{4005}
3
a
1
+
5
a
2
+
...
+
4005
a
2002
.
algebra
polynomial
algebra unsolved