3/a+a-3/a+5 выполни действие

3/a+a-3/a+5=a+5...........................

 3/a + (a-3)/(a + 5) = (3*(a  + 5) + a(a - 3)) /a (a + 5) = (3a + 15 +a^2 - 3a)/a(a + 5) =      =(a^2 + 15)/a(a + 5)