1/2*4+1/4*6+1/6*8+····+1/2006*2008=1/2*(1/2-1/4+1/4-1/6+...+1/2006-1/2008)=1/2*(1/2-1/2008)=1/2*1003/2008=1003/4016 步骤1中为什么要乘以½

计算1/2×4+1/4×6+1/6×8+···+1/2006×2008 计算：(2+4+6+8+···+100)-(1+3+5+···+99) 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=几 1/2*4+1/4*6+1/6*8+····+1/2006*2008=几 1/2*4+1/6*8+······+1/2006*2008+1/4*6+1/8*10+······+1/2004*2006=?*是乘号 /是分数线 1×2+2×3+3×4+4×5+5×6+6×7+7×8+8×9··········+100×101等于多少?1×2+2×3+3×4+4×5+5×6+6×7+7×8+8×9··········+n(n+1)这个要代数式. (2+4+6+8+······+100)—(1+3+5+7+······+99)等于几 （1+3+5++7+9······+2011）-（2+4+6+8······+2012）= 把1 9填入81格方框,不能重复· · 4 · · 5 · 6 ·9 · · 3 · · · 5 17 · · 6 · · · · 3· · 9 · 1 6 · 4 ·· 2 · 4 · · · 8 ·· 4 · 7 · · 5 · ·5 · · · · 7 · · 84 1 · · · 8 · · 5· 8 · 9 · · 6 · 4 1+2+3+4+5+6+7+8+9······+99=?1 俗语和名句的填空1······,自知之明.2······,行必果.3工欲善其事,······.4临渊羡鱼,······.5非学无以广才,······.6······,福兮祸之所伏.7项庄舞剑,······.8······,人以群 4/3×6/5×8/7×······×(2n+2)/(2n+1)求积 证明1·3·5·····(2n-1)/2·4·6·····2n 2011红领巾快乐数独答案一2·····4·9·631·4·8·8··97··3··3··2·95···95·86···15·3··7··9··47··5·7·3·182·3·4·····7二7·1·8·3·····413·6·2·6···4·8·8·5·1·2·61·····94·2·9·4·7·8· 计算 1/2*4+1/4*6+1/6*8+······+1/98*100的简便方法 2*4分之1加4*6分之1+6*8分之1······+48*50分之1=? 1/(2×4)+1/(4×6)+1/(6×8)+1/(8×10)+·····+1/(2008×2010)的算法（详细过程）,