Question 9
Find distinct numbers $a$, $b$, $c$, $d$ such that:
$$
\frac{1}{2011} = \frac{a}{a+1} + \frac{b}{b+1} - \frac{c}{c+1} - \frac{d}{d+1}
$$
$$
\frac{1}{2011} = \frac{a}{a+1} + \frac{b}{b+1} - \frac{c}{c+1} - \frac{d}{d+1}
$$
MathNet 2011 Question 9
Math Olympiad Vault · MathNet 2011