Question 16
Show that for all real numbers $a, b, c$,
$$
a^{6} + b^{6} + c^{6} - 3 a^{2} b^{2} c^{2} \geq \frac{1}{2}(a-b)^{2}(b-c)^{2}(c-a)^{2}
$$
$$
a^{6} + b^{6} + c^{6} - 3 a^{2} b^{2} c^{2} \geq \frac{1}{2}(a-b)^{2}(b-c)^{2}(c-a)^{2}
$$
MathNet 2013 Question 16
Math Olympiad Vault · MathNet 2013