Question

Rezultatul calculului: $\frac{a}{a+1} + \frac{1}{a-1} + \frac{1}{a+1} - \frac{a}{a-1}$

Answer 1

C.E.
a≠1;a≠-1

(a+1)/(a+1)+(1-a)/(a-1)=1-(a-1)/(a-1)=1-1=0
as simple as that !