Question 132
Find the largest positive number $\lambda$ such that
$$
| \lambda xy + yz | \le \frac{\sqrt{5}}{2}, \text{ where } x^2 + y^2 + z^2 = 1.
$$
$$
| \lambda xy + yz | \le \frac{\sqrt{5}}{2}, \text{ where } x^2 + y^2 + z^2 = 1.
$$
MathNet 2008-part-01 — 165 problems (EN–VI) Question 132
Math Olympiad Vault · MathNet 2008-part-01 — 165 problems (EN–VI)