用洛必达法则求极限 11题?原式=e^(1/x^2)/[1/x^2]令t=1/x^2=无穷大原式=e^t/t=e^t=无穷大(洛必达法则)
x^(-1/2)=u, x^2=u^(-4)lim《x->0》{x^2*e^[x^(-1/2)]}=lim《u->无穷》[u^(-4)*e^u]=lim《u->无穷》[e^u/u^4]=lim《u->无穷》[e^u/4!] (连续4次洛必达法则)极限不存在,趋于无穷