Question

люди добрые, помогите​

Answer 1

1) (a/a+1):(1-a/a+1) = a+a+1/a+1 : a+1-a/a+1 = a+a+1/a+1 : 1/a+1 = 2a+1/a+1 * (a+1) = 2a+1