was ergeben diese Brüche am Ende?

Question

Was ist (1/a+1/b):(1/a-1/b)? 

Vielen DANK!!!

Answer 1

(1/a + 1/b) : (1/a - 1/b)

= (b/(a·b) + a/(a·b)) : (b/(a·b) - a/(a·b))

= (a + b)/(a·b) : ((b - a)/(a·b))

= (a + b) : (b - a)

Answer 2

(1/a+1/b):(1/a-1/b)=((a+b)/(ab))/((b-a)/(ab))= (a+b)/(b-a)