Question 99
Show that for all $x, y \in \mathbb{R}$:
$$
x^4 + y^4 + 18 \ge 12xy.
$$
When do we get equality?
$$
x^4 + y^4 + 18 \ge 12xy.
$$
When do we get equality?
MathNet 2026 — Part 06 Question 99
Math Olympiad Vault · MathNet 2026 — Part 06
Math Olympiad Vault · MathNet 2026 — Part 06