Obliczić pole obszaru zawartego między osią Ox i krzywą y=1/1+x²

  P = ∫od -∞ do +∞ [dx/(1 + x²)] = lim A -->-∞, B -->+∞ ∫ od A do B  [dx/(1 +x²)] = = lim A --> -∞, B--> +∞ ( arctg B - arctg A)= π/2 - (-π/2) = π ==========================================================