1/(2*4)+1/(4*6)+1/(6*8)+········+1/(2006*2008)等于?
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1/(2*4)+1/(4*6)+1/(6*8)+········+1/(2006*2008)等于?
1/(2*4)+1/(4*6)+1/(6*8)+········+1/(2006*2008)等于?
1/(2*4)+1/(4*6)+1/(6*8)+········+1/(2006*2008)等于?
1/(2*4)+1/(4*6)+1/(6*8)+········+1/(2006*2008)
=1/2*(1/2-1/4)+1/2*(1/4-1/6)+……+1/2*(1/2006-1/2008)
=1/2*(1/2-1/4+1/4-1/6+……+1/2006-1/2008)
=1/2*(1/2-1/2008)
=1003/4016
1/(2*4) = 0.5 * (1/2-1/4)
后面每个都这么拆
最后变为 0.5 * (1/2-1/4 + 1/4-1/6 + ... + 1/2006-1/2008)
= 0.5 * (1/2- 1/2008) = 1003/4016
-1/2+(-1/6)-(-1/4)-2/3
(2/1-4/1)+(4/1-6/1)+(6/1-8/1)+.+(48/1-50/1)
10,1,8,1,6,2,4,6,2,().
(1/2+1/3+1/4+1/6)*24
-72×(1/4+1/6+1/2)
计算:-72×(1/4+1/6-1/2)
(1/4+1/6-1/2)×12
(1/4+1/6-1/2)×12
求和:1+(1+2)+(1+2+4)+(1+2+4+6)+(1+2+4+.2^n-1)
1/2-(3/4-3/8),1/2+1/4-1/6 ,2/3+(1/2+1/4),1/2-(3/4-3/8),1/2+1/4-1/6 ,2/3+(1/2+1/4),
1/2-(3/4-3/8), 1/2+1/4-1/6 , 2/3+(1/2+1/4),1/2-(3/4-3/8), 1/2+1/4-1/6 , 2/3+(1/2+1/4),
1/2-(3/4-3/8),1/2+1/4-1/6 ,2/3+(1/2+1/4),1/2-(3/4-3/8),1/2+1/4-1/6 ,2/3+(1/2+1/4),
1/(2*4)+1/(4*6)+1/(6*8)+.+1/(2008*2010)
1 3/4-5/6-(+1 1/6)-(-1/2)
(1+2/1)(1+4/1)(1+6/1).(1+10/)(1-3/1)(1—5/1).(1-9/1)
1/2+1/(2+4)+1/(2+4+6)+...1/(2+4+6+...2n),求和
1/(2+4)+1/(4+6)+1/(6+8)+…1/(2010+2012)怎么做
探究并计算:1/(2*4)+1/(4*6)+1/(6*8)+…+1/(2006*2008)