Question 130
Let $a$, $b$ and $c$ such as $$
|a-b| \geq |c|,\ |b-c| \geq |a| \text{ and } |c-a| \geq |b|.
$$ prove that one of three numbers $a$, $b$ and $c$ is the sum of the other two.
|a-b| \geq |c|,\ |b-c| \geq |a| \text{ and } |c-a| \geq |b|.
$$ prove that one of three numbers $a$, $b$ and $c$ is the sum of the other two.