(0.1+0.21+0.31)*(0.21+0.31+0.41)-(0.1+0.21+0.31+0.41)*(0.21+0.31)的简便计算
展开全部
答：设0.1+0.21+0.31=a，0.21+0.31=b。则：a-b=0.1
(0.1+0.21+0.31)× (0.21+0.31+0.41)-(0.1+0.21+0.31+0.41)×(0.21+0.31)
=a(b+0.41)-(a+0.41)b
=ab+0.41a-ab-0.41b
=0.41(a-b)
因为：a-b=0.1
所以：原式=0.41×0.1=0.041
(0.1+0.21+0.31)× (0.21+0.31+0.41)-(0.1+0.21+0.31+0.41)×(0.21+0.31)
=a(b+0.41)-(a+0.41)b
=ab+0.41a-ab-0.41b
=0.41(a-b)
因为：a-b=0.1
所以：原式=0.41×0.1=0.041
已赞过
已踩过<
评论
收起
你对这个回答的评价是？
展开全部
(0.1+0.21+0.31)*(0.21+0.31+0.41)-(0.1+0.21+0.31+0.41)*(0.21+0.31)
=(0.1+0.21+0.31)*(0.21+0.31+0.41)-(0.1+0.21+0.31)*(0.21+0.31)-0.41*(0.21+0.31)
=(0.1+0.21+0.31)*(0.21+0.31+0.41-(0.21+0.31))-0.41*(0.21+0.31)
=(0.1+0.21+0.31)*0.41-0.41*(0.21+0.31)
=0.41*(0.1+0.21+0.31-(0.21+0.31))
=0.41*0.1
=0.041
=(0.1+0.21+0.31)*(0.21+0.31+0.41)-(0.1+0.21+0.31)*(0.21+0.31)-0.41*(0.21+0.31)
=(0.1+0.21+0.31)*(0.21+0.31+0.41-(0.21+0.31))-0.41*(0.21+0.31)
=(0.1+0.21+0.31)*0.41-0.41*(0.21+0.31)
=0.41*(0.1+0.21+0.31-(0.21+0.31))
=0.41*0.1
=0.041
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
