Question

请问这个式子怎么化解？

Answer 1

把三次根号下x看成t
相当于(1-t^3)/(1-t)=1+t+t^2，值为3

Answer 2

1-x= [1-x^(1/3)].[1+x^(1/2) + x^(2/3)]
lim(x->1) ( 1-x)/(1- x^(1/3))
=lim(x->1) [1+x^(1/2) + x^(2/3)]
=3