1.9－1.9乘以（1.9-1.9）怎么简便？

1.9-1.9*(1.9-1.9)
=1.9-1.9*0
=1.9-0
=1.9

看我的

1.9-1.9*(1.9-1.9)
=1.9-1.9*0
=1.9-0
=1.9
祝你学业有成

先算括号里,接着算二级运算,最后算一级运算,得最后答案为1.9
无简便 ,初级运算

1.9*1.9
=(2-0.1)*(2-0.1)
=2*2-2*2*0.1+0.1*0.1
=4-0.4+0.01
=3.61

答案：1.9

1.9-1.9*(1.9-1.9)=
1.9-1.9*0=1.9

1.9－1.9*（1.9-1.9）
=1.9-0
=1.9