如何巧算(1+1⼀2)×(1-1⼀2)×(1+1⼀3)×(1-1⼀3)...(1+1⼀99)×(1-1⼀99)

2025-03-17 18:13:13
推荐回答(1个)
回答1:

原式=(3/2)(1/2)(4/3)(2/3)(5/4)(3/4)……(99/98)(97/98)(100/99)(98/99)
列出来分子分母错位相消!最后剩下100/(2*99)=50/99