Question 179
Let $a$, $b$, $c$ be positive real numbers such that $a b c = 1$. Simplify
$$
\frac{1}{1+a+ab} + \frac{1}{1+b+bc} + \frac{1}{1+c+ca}.
$$
$$
\frac{1}{1+a+ab} + \frac{1}{1+b+bc} + \frac{1}{1+c+ca}.
$$
MathNet 2018-part-06 — 181 problems (EN–VI) Question 179
Math Olympiad Vault · MathNet 2018-part-06 — 181 problems (EN–VI)