1/2+(1/3+2/3)+(1/4+2/4+3/4)+(1/5+2/5+3/5+4/5)+.+(1/50+.+49/5
来源:学生作业帮 编辑:搜搜做题作业网作业帮 分类:数学作业 时间:2024/07/27 04:43:15
1/2+(1/3+2/3)+(1/4+2/4+3/4)+(1/5+2/5+3/5+4/5)+.+(1/50+.+49/50)怎么解?
![1/2+(1/3+2/3)+(1/4+2/4+3/4)+(1/5+2/5+3/5+4/5)+.+(1/50+.+49/5](/uploads/image/z/6389125-61-5.jpg?t=1%2F2%2B%281%2F3%2B2%2F3%29%2B%281%2F4%2B2%2F4%2B3%2F4%29%2B%281%2F5%2B2%2F5%2B3%2F5%2B4%2F5%29%2B.%2B%281%2F50%2B.%2B49%2F5)
原式=1/2+2*1/2+3*1/2+4*1/2+.+49*1/2
=1/2(1+2+3+4+.+49)
=1/2*725
=725/2
=1/2(1+2+3+4+.+49)
=1/2*725
=725/2
1/2+(1/3+2/3)+(1/4+2/4+3/4)+(1/5+2/5+3/5+4/5)+.+(1/50+.+49/5
1*2+2*3+3*4+4*5+5*6+……48*49+49*50
5/(2*1)+5/(2*3)+5/(3*4)……5/(49*50)等于多少
1.1/2+1/3+2/3+1/4+2/4+3/4+1/5+2/5+3/5+4/5+...+49/50
1/2×3+1/3×4+1/4×5+……+1/49×50
1/2*3 + 1/3*4 + 1/4*5 + .1/49*50
1-2+3-4+5-6...+49-50=?
2*1+4*3+6*5+8*7.+50*49
1*1-2*2+3*3-4*4+5*5-6*6+…+49*49-50*50=
2*3分之1+3*4分之1+4*5分之1.+49*50分之1
1 2 3 4 5
.1,2,3,4,5,