sqrt(x-3)=3/2 x-3=9/4 x=21/4=5,25
<span>(x-2)/(x^2-1)-(1-2x)/(x^2-1)=</span>(x-2-1+2x)/(x^2-1)=(3x-3)/(x-1)(x+1)=3(x-1)/(x-1)(x+1)=3/x+1