Question 84
Find all positive integers $n$ satisfying the inequality
$$
\cos(\pi\sqrt{n^2+n}) \ge 0.
$$
$$
\cos(\pi\sqrt{n^2+n}) \ge 0.
$$
MathNet 2005 — Part 03 Question 84
Math Olympiad Vault · MathNet 2005 — Part 03
Math Olympiad Vault · MathNet 2005 — Part 03