2⼀1x2x3+2⼀2x3x4+2⼀3x4x5+2⼀4x5x6+...+2⼀98x99x100=

2024-11-16 04:32:17
推荐回答(1个)
回答(1):

解:原式=(1/1*2-1/2*3)+(1/2*3-1/3*4)+……(1/98*99-1/99*100)
=1/1*2-1/99*100
=49499/99000