1/(1*2)+1/(2*3)+1/(3*4)+L+1/(100*101)=

来源:学生作业帮助网 编辑:作业帮 时间:2024/11/28 07:12:53
1/(1*2)+1/(2*3)+1/(3*4)+L+1/(100*101)=
x)302FZ`XDS240240ԴI*'V~ IXz2[ C]C}: d!T*uA$L-X6T!6օ+2FҀP9yvPـ9tXt_= 42ԏ1o=0Ip7ƥ@`h8/g<хZHHD@: , A HAJ

1/(1*2)+1/(2*3)+1/(3*4)+L+1/(100*101)=
1/(1*2)+1/(2*3)+1/(3*4)+L+1/(100*101)=

1/(1*2)+1/(2*3)+1/(3*4)+L+1/(100*101)=

1/(1*2)+1/(2*3)+……+1/(100*101)
=(1-1/2)+(1/2-1/3)+……+(1/100-1/101)
=1-1/2+1/2-1/3+1/3-……-1/100+1/100-1/101
=1-1/101
=100/101

有规律:1/n-1/(n+1)=1/[n*(n+1)]
原式=1-1/101=100/101


1/(1*2)+1/(2*3)+……+1/(100*101)
=(1-1/2)+(1/2-1/3)+……+(1/100-1/101)
=1+(1/2-1/2)+(1/3-1/3)+……+(1/100-1/100)-1/101
=1-1/101
=100/101
附上
1/(1*2)=1-1/2
1/(2*3)=1/2-1/3
………………
1/n(n+1)=1/n-1/(n+1)