十一、求下列曲线的水平和铅垂渐近线-|||-1. =(e)^2x-|||-2. =(e)^-(x^2)-|||-3. =dfrac ({e)^x}(1+x)-|||-4. =dfrac (sqrt {(x+1)(x+2))}(x)-|||-5. =(e)^dfrac (1{x)}-|||-6. =c+dfrac ({a)^3}({(x-b))^2}