Uprostit` virazhenie: a/a+c - 2ac/a^2-c^2 + c/a-c

a/(a+c) -2ac/(a-c)(a+c) +c/(a-c)=(a²-ac-2ac+ac+c²)/(a-c)(a+c)=(a²-2ac+c²)/(a-c)(a+c)==(a-c)²/(a-c)(a+c)=(a-c)/(a+c)