简便运算1234×2345-1233×2346明要交!快

问题描述:

简便运算1234×2345-1233×2346
明要交!快

1234x2345-1233x(2345+1)
=2345(1234-1233)-1233
=2345-1233
=1112

原式=1234*2345-1233*2346+2346-2346
=1234*2345-1234*2346+2346
=1234(2345-2346)+2346
=-1234+2346
=1112