For all positive real numbers \( a, b, c \), prove that
\[ \frac{(a^2 + bc)^2}{b + c} + \frac{(b^2 + ca)^2}{c + a} + \frac{(c^2 + ab)^2}{a + b} \geq \frac{2abc(a + b + c)^2}{ab + bc + ca}. \]
Solution 1Solution 2Solution 3
