(x + (3-x^2)/(x+1)) : (x+5)/(x^2+2x+1) = (x^2+x+3-x^2)/(x+1)*(x+1)^2/(x+5) = (x+3)(x+1)/(x+5)
<span>(x+1)^2*(x^2+2x)=0</span>