(1+0.12+0.34)x(0.12+0.34+0.56)-(1+0.12+0.34+0.56)x(0.12+0.34)要简便计算
问题描述:
(1+0.12+0.34)x(0.12+0.34+0.56)-(1+0.12+0.34+0.56)x(0.12+0.34)
要简便计算
答
(1+0.12+0.34)x(0.12+0.34+0.56)-(1+0.12+0.34+0.56)x(0.12+0.34)
=(0.34+0.56+0.12+0.34)x(0.12+0.34+0.56)-(1+0.12+0.34+0.56)x(0.12+0.34+0.56-0.56)
=0.34x(0.12+0.34+0.56)+(0.56+0.12+0.34)x(0.12+0.34+0.56)-(0.12+0.34)
-(0.12+0.34+0.56)x(0.12+0.34+0.56)+0.56x(0.12+0.34+0.56)
合并同类项,约去相同的式子
=(0.34+0.56)x(0.12+0.34+0.56)-0.12-0.34
=(0.12+0.34+0.56)-0.12-0.34
=0.56