1/1*2+1/2*3+1/3*4+…+1/9*10
1个回答
1/1*2+1/2*3+1/3*4+…+1/9*10
=1-1/2+1/2-1/3+1/3-1/4+……+1/9-1/10
=1-1/10
=9/10
相关问题
(2√1+1√2)/1+(3√2+2√3)/1+(1+4√3+3√4)/1+……(10√9+9√10)/1=?
1/2+(1/3+2/3)+(1/4+2/4+3/4)+.+(1/10+2/10+……+9/10)
化简:[1/(2+√2)]+[1/(3√2+2√3)]+[1/(4√3+3√4)]+……+[1/(10√9+9√10)]
1=1;1—4=—〔1+2〕=—3;1—4+9=1+2+3=6;1—4+9—16=—〔1+2+3+4〕=—10…….第1
已知1*1+2*2+3*3+4*4+……+9*9+10*10=355,求1*2+2*3+3*4+……9*10+10*11
1/(1*2)+1/(2*3)+1/(3*4)+K+1/(8*9)+1/(9*10)=?
已知数列an:1/2,1/3+2/3,1/4+2/4+3/4,..,1/10+2/10+3/10+..+9/10,..,
1/1*2*3+1/2*3*4+1/3*4*5+.+1/8*9*10
|1-1/2|+|1/2-1/3|+|1/3-1/4|+...|1/9-1/10|
(1+1/2+1/3+.1/9)*(1/2+1/3+1/4+.1/10)减(1+1/2+1/3+...+1/10)*(1