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APMO
2009 APMO
2
2
Part of
2009 APMO
Problems
(1)
Sum of 5 fractions
Source: APMO 2009 Q.2
3/13/2009
Let
a
1
a_1
a
1
,
a
2
a_2
a
2
,
a
3
a_3
a
3
,
a
4
a_4
a
4
,
a
5
a_5
a
5
be real numbers satisfying the following equations: \frac{a_1}{k^2\plus{}1}\plus{}\frac{a_2}{k^2\plus{}2}\plus{}\frac{a_3}{k^2\plus{}3}\plus{}\frac{a_4}{k^2\plus{}4}\plus{}\frac{a_5}{k^2\plus{}5} \equal{} \frac{1}{k^2} for k \equal{} 1, 2, 3, 4, 5 Find the value of \frac{a_1}{37}\plus{}\frac{a_2}{38}\plus{}\frac{a_3}{39}\plus{}\frac{a_4}{40}\plus{}\frac{a_5}{41} (Express the value in a single fraction.)
linear algebra
algebra