49×49+49+49×49怎样简便运算

来源:学生作业帮助网 编辑:作业帮 时间:2024/04/28 12:53:27
49×49+49+49×49怎样简便运算

49×49+49+49×49怎样简便运算
49×49+49+49×49怎样简便运算

49×49+49+49×49怎样简便运算
=49x(49+1+49)
=49x99
=49x(100-1)
=4900-49
=4851

把49看成50-1


原式=
49*49+1*49+7+49*49
=99*49
=100*49-99
=4900-99
=4801

49×49+49+49×49
=﹙50-1﹚×49+49+﹙50-1﹚×49
=50×49-49+49+50×49-49
=49×﹙50+50-1﹚
=4900-49
=4851