Răspuns:
Explicație pas cu pas:
E(x)=[(2/(x²-1)+3/(x-1)+3/(x+1)]:2/(x-1)
a) domeniul de definitie: R/{-1,1}
b) E(x)=[2+3(x+1)+3(x-1)]/(x-1)(x+1)·(x-1)/2=(2+3x+3+3x-3)/(x+1)·1/2=
=(6x+2)/2·1/(x+1)=(3x+1)/(x+1)
c)E(n)=(3n+3-2)/(n+1)=3-2/(n+1)
n+1=±1 ⇒n=0 si n=-2
n+1=±2 ⇒n=1 si n=-3 ⇒n∈{-3,-2,0,1}
