1/1x2+1/2x3+1/3x4+.+1/2011x2012=多少
1个回答
1/1x2+1/2x3+1/3x4+.+1/2011x2012
=1-1/2+1/2-1/3+1/3-1/4+.+1/2011-1/2012
=1-1/2012
=2011/2012
相关问题
1/1x3+1/2x4+1/3x5+…+1/2011x2013+1/2012x2014=多少
x1x2x3.x2011=1x1-x2x3.x2011=1x1x2-x3x4.x2011=1.x1x2.x2010-x2
x/1*2+x/2*3+……+x2011*2012=2011
用规律计算(-1x1/2)+(-1/2x1/3)+(-1/2011x1/2012)
(1x2)分之1+(2x3)分之1+(3x4)分之1+…+(2011x2012)分之1=
计算1/2+1/(3x2)+1/(4x3)+.+1/(2011x2010)=?
=1;2!=2x1;3!=3x2x1;4!=4x3x2x1……计算:2012!分之2013!
1/1x2+1/2x3+1/3x4+.+1/99x100+1/2011x2012 五分钟之内求高人把它解出来
x^4+2011x^2+2010x+2011 分解因式 提示:x^3-1=(x-1)(x^2+x+1)
|x+2|+|y-3|=0则x-y=多少 1+(-2)+3+(-4)+5+(-6)+.+2011+(-2012)