作业帮如图21.22两题
来源：学生作业帮助网 编辑：作业帮 时间：2024/05/07 16:07:01
如图21.22两题
如图21.22两题
如图21.22两题
21
x=(√2+1)-(√2-1)=2
带入进去算值更简单一些.
(1/3-2/3)/3=-1/9
22
原式=x(x-1/2)(x+1/2)^2-(x-1/2)^2*(x+1/2)^2-1/2x^2(x-1/2)
=1/2(x-1/2)(x+1/2)^2-1/2x^2(x-1/2)=1/2(x-1/2)(x+1/4)=1/2x^2-1/8x-1/16