(1)8*9/1+9*10/1+10*11/1+.99*100/1(2) 2/1+(3/1+3/2)+(4/1+4/2+4/3)+(5/1+5/2+5/3+5/4)+.+(60/1+60/2+60/3+.+60/59)我把分子与分母的位置调转了
来源:学生作业帮助网 编辑:作业帮 时间:2024/08/26 03:54:56
![(1)8*9/1+9*10/1+10*11/1+.99*100/1(2) 2/1+(3/1+3/2)+(4/1+4/2+4/3)+(5/1+5/2+5/3+5/4)+.+(60/1+60/2+60/3+.+60/59)我把分子与分母的位置调转了](/uploads/image/z/6114517-61-7.jpg?t=%EF%BC%881%EF%BC%898%2A9%2F1%2B9%2A10%2F1%2B10%2A11%2F1%2B.99%2A100%2F1%282%29+2%2F1%2B%283%2F1%2B3%2F2%29%2B%EF%BC%884%2F1%2B4%2F2%2B4%2F3%EF%BC%89%2B%EF%BC%885%2F1%2B5%2F2%2B5%2F3%2B5%2F4%EF%BC%89%2B.%2B%2860%2F1%2B60%2F2%2B60%2F3%2B.%2B60%2F59%29%E6%88%91%E6%8A%8A%E5%88%86%E5%AD%90%E4%B8%8E%E5%88%86%E6%AF%8D%E7%9A%84%E4%BD%8D%E7%BD%AE%E8%B0%83%E8%BD%AC%E4%BA%86)
(1)8*9/1+9*10/1+10*11/1+.99*100/1(2) 2/1+(3/1+3/2)+(4/1+4/2+4/3)+(5/1+5/2+5/3+5/4)+.+(60/1+60/2+60/3+.+60/59)我把分子与分母的位置调转了
(1)8*9/1+9*10/1+10*11/1+.99*100/1
(2) 2/1+(3/1+3/2)+(4/1+4/2+4/3)+(5/1+5/2+5/3+5/4)+.+(60/1+60/2+60/3+.+60/59)
我把分子与分母的位置调转了
(1)8*9/1+9*10/1+10*11/1+.99*100/1(2) 2/1+(3/1+3/2)+(4/1+4/2+4/3)+(5/1+5/2+5/3+5/4)+.+(60/1+60/2+60/3+.+60/59)我把分子与分母的位置调转了
假如你把分子与分母的位置调转了,那(1)题应该是这样的:
1/8*9+1/9*10+1/10*11+...+1/99*100
=(1/8 - 1/9)+(1/9 - 1/10)+(1/10 - 1/11)+...+(1/99 - 1/100)
=1/8 - 1/100
=23/200
那(2)题应该是这样的:
1/2+(1/3+2/3)+(1/4+2/4+3/4)+(1/5+2/5+3/5+4/5)+...+(1/60+2/60+3/60+...+58/60+59/60)=1/2+(1+2)/3+(1+2+3)/4+...+(1+2+...+59)/60
第n项为:
(1+2+.+n)/(n+1)
=n(n+1)/2(n+1)
=n/2
原式=(1+2+3+...+59)/2
=(1+59)59/2/2
=885
你打错了分子与分母的位置了吧?