观察下列各式: 1X2=1⼀3(1x2x3-0x1x2) 2x3=1⼀3(2x3x4-1x2x3) 3x4=1⼀3(3x4x5-2x3x4) ```

计算:3x(1x2+2x3+3x4+```+99x100)= ( )A.97x98x99 B.98x99x100 C.99x100x101 D.100x101x102
2024-12-14 03:13:15
推荐回答(1个)
回答1:

3*(1x2+2x3+3x4+...+99x100)
=3*1/3*(1x2x3-0x1x2+2x3x4-1x2x3+3x4x5-2x3x4+99x100x101-98x99x100)
=99x100x101

选 C