先化简再求值1/x+2-x²+2x+1/x+2÷x²-1/x-1,其中x=根号2-2
1个回答
展开全部
1/(x+2) - (x²+2x+1)/(x+2) ÷(x²-1)/(x-1)
=1/(x+2) - (x+1)²/(x+2) ÷ (x+1)
=1/(x+2) - (x+1)/(x+2)
=(1-x-1)/(x+2)
=-x/(x+2)
=-(根号2 -2)/(根号2-2+2）
=（2-根号2)/根号2
=根号2 -1
=1/(x+2) - (x+1)²/(x+2) ÷ (x+1)
=1/(x+2) - (x+1)/(x+2)
=(1-x-1)/(x+2)
=-x/(x+2)
=-(根号2 -2)/(根号2-2+2）
=（2-根号2)/根号2
=根号2 -1
本回答由提问者推荐
已赞过
已踩过<
评论
收起
你对这个回答的评价是？
推荐律师服务：
若未解决您的问题，请您详细描述您的问题，通过百度律临进行免费专业咨询
