Question

Найди z, если lgz=lg(k2−u2)−2lg(k+u).

Answer 1

lgz=lg(k²−u²)−2lg(k+u).

lgz=lg(k²−u²)−lg(k+u)²

lgz=lg(k−u)(k+u)/(k+u)²

lgz=lg(k−u)/(k+u)

z=(k−u)/(k+u)