1/3*4+1/4*5+1/5*6+1/6*7+……+1/99*100=?求规律!

数学题(1/4+1/5+1/6+...+1/671)(1/3+1/4+1/5+..+1/670)-(1/3+1/4+1/5+...+1/671)(1/4+1/(1/4+1/5+1/6+...+1/671)(1/3+1/4+1/5+..+1/670)-(1/3+1/4+1/5+...+1/671)(1/4+1/5+1/6+...+1/670）=? 简算：1/1*2+1/2*3+1/3*4+1/4*5+1/5*6 巧算：(1+1/2+1/3+1/4+1/5)*(1/2+1/3+1/4+1/5+1/6)-(1+1/2+1/3+1/4+1/5+1/6)*(1/2+1/3+1/4+1/5)(1+1/2+1/3+1/4+1/5)*(1/2+1/3+1/4+1/5+1/6)-(1+1/2+1/3+1/4+1/5+1/6)*(1/2+1/3+1/4+1/5)===== (-60)/(1/3-1/4+1/5-1/6) please 1/3*4+1/4*5+1/5*6+1/6*7+.1/99*100=? 2×3/1+3×4/1+4×5/1+5×6/1+.199×200/1=? 1/1*3+1/2*4+1/3*5+1/4*6+.+1/100*102=? 1+1+1+1+11+-1-1-1-1-2-3-4-5-6等于 1-1/2+1/3-1/4+1/5-1/6+1/7.-1/50=? 1/2*1/3+1/3*1/4+1/4*1/5+1/5*1/6 （简便方法） [2^4+1/4)(4^4+1/4)(6^4+1/4)(8^4+1/4)(10^4+1/4)】/[1^4+1/4)(3^4+1/4)(5^4+1/4)(7^4+1/4)(9^4+1/4)] (1/4+1/5+1/6+...+1/671)(1/3+1/4+1/5+...+1/670)-(1/3+1/4+1/5+...+1/671)(1/4+1/5+1/6+...+1/670)= 1/1*2*3+1/2*3*4+1/3*4*5+1/4*5*6---------+1/48*49*50 1+1+1+1+1+1+1+1+1+2+5+4+8+3+6+2+1+4等于多少? 1/2{1/3[1/4(1/5x-1)-6]+4}=1 1.（1+1/2+1/3+1/4）*（1/2+1/3+1/4+1/5）-（1+1/2+1/3+1/4+1/5）*（1/2+1/3+1/4）=2.（1+1/2+1/3+1/4+1/5）*（1/2+1/3+1/4+1/5+1/6）-（1+1/2+1/3+1/4+1/5+1/6）*（1/2+1/3+1/4+1/5）= 1*1/2+1/2*1/3+1/3*1/4+1/4*1/5+1/5*1/6+1/6*1/7用简便方法怎么做? 矩阵特征值问题,怎样让矩阵的特征值变小1 3 3 3 5 5 7 7 7 9;1/3 1 2 3 4 4 5 5 6 8;1/3 1/2 1 2 4 5 6 5 7 7;1/3 1/3 1/3 1/2 4 5 6 7 8 7;1/5 1/4 1/4 1/4 1 3 5 5 6 7;1/5 1/4 1/5 1/5 1/3 1 3 3 1 5;1/7 1/5 1/6 1/6 1/5 1/3 1 1 3 7;1/7 1/5 1/5