[1/(x²+4x+4)+1/(x²+2x)]÷(x+1)/(x+2)=[1/(x+2)²+1/x(x+2)]÷(x+1)/(x+2)=[1/(x+2)+1/x]÷(x+1)=[(x+x+2)/x(x+2)]÷(x+1)=2(x+1)/x(x+2)÷(x+1)=2/x(x+2)=2/[3*(3+2)]=2/15如果不懂，请追问，祝学习愉快！
