For a class of functions H : ( 0 , ∞ ) × ℝ + 2 → ℝ , including discontinuous functions of Carathéodory type, we establish that ∫ ℝ N H ( | x | , u ( x ) , v ( x ) ) d x ≤ ∫ ℝ N H ( | x | , u * ( x ) , v * ( x ) ) d x , where u * ( x ) and v * ( x ) denote the Schwarz symmetrizations of nonnegative functions u and v .