一道找规律题目

来源:百度知道 编辑:UC知道 时间:2024/05/18 18:40:29
1/2=1/1*2=1/1-1/2,1/6=1/2*3=1/2-1/3,1/12=1/3*4=1/3-1/4
1.通过观察,你得出什么结论?用含N(N为正整数)的等式表示:
2.利用你得出的结论,计算:
1/(a-1)(a-2)+1/(a-2)(a-3)+1/(a-3)(a-4)+1/(a-4)(a-5)

1/n(n+1)=1/n-1/n+1

原式=1/(a-1)-1/(a-2)+1/(a-2)-1/(a-3)+1/(a-3)-1/(a-4)+1/(a-4)-1/(a-5)
=1/(a-1)-1/(a-5)

1.1/N(N+1)=1/N-1/(N+1)
2.1/(a-1)(a-2)+1/(a-2)(a-3)+1/(a-3)(a-4)+1/(a-4)(a-5)=
1/(a-1)-1/(a-5)

晕倒,这个样子你还出出来啊,完全告诉你答案了,还找什么规律

1.1/N*N-1=1/(N-1)-1/N
2.1/(a-1)-1/(a-5)

1) 1/N*(N+1)=1/N-1/(N+1)
2) 1/(a-1)-1/(a-5)