It is proved that (a + b) (B + C) (c + a) is greater than or equal to 8abc, and (a, B, c) are positive real numbers

It is proved that (a + b) (B + C) (c + a) is greater than or equal to 8abc, and (a, B, c) are positive real numbers

Because (a + b) (B + C) (c + a) ≥ 8abc is the multiplication of (a + b) (B + C) (c + a) ≥ 8abc if and only if a = b = C