✔ 最佳答案
2^(1/3) -1
=1/[4^(1/3)+2^(1/3)+1]
=3/[3*4^(1/3)+3*2^(1/3)+3]
=3/[2+3*4^(1/3)+3*2^(1/3)+1]
=3/[2^(1/3)+1]^3
[2^(1/3) -1]^(1/3)
= [3^(1/3)]/[2^(1/3)+1]
=[3^(1/3)]*[4^(1/3)-2^(1/3)+1] / 3
=(12/27)^(1/3)+(- 6/27)^(1/3)+(3/27)^(1/3)
=a^(1/3)+b^(1/3)+c^(1/3)
所以a=12/27,b= - 6/27,c= 3/27
a+b+c = 9/27 =1/3...........(解答)
同樣是參考老王的作法,不過有略作修改.....................