5/3x6/1x5= (10/1+4/1)x4= (9/8+27/4)x27= 39x38/27= 2/1x15/4+3/1x2/1= 7/5x16x5/21= 12x(2/1-3/1+4/1)=7/12x(6/7+3/14)= 5/1+9/4x8/3+6/5= (5/1-7/1)x70= 97x96/5= 15x7/3+15x7/4= (9/8+4/3-3/2)x72= 5/3x8+5/3x2= 72x(2/1-3/1+4/1)= （这些要简便运算的,上

1x2+2x3+3x4+4x5+5x6---+99x100=? x1-x2+x3=1x2-x3+x4=21若x1,x2,x3,x4,x5满足方程组 x3-x4+x5=3x4-x5+x1=4x5-x1+x2=5求x2 x3 x4的值2已知 x1+x4+x6+x7=39 x2+x4+x5+x7=49 x3+x5+x6+x7=41 x4+x7=13 x5+x7=14 x6+x7=9 x1+x2+x3+x4+x5+x6+x7=9求x7的值若x1,x2,x3,x4,x5满足方程组 x1-x 1/1x3+1/2x4+1/3x5+1/4x6+...+1/10x12 1/1x3+1/2x4+1/3x5+1/4x6+...+1/100x102=? 1x2+2x3+3x4+4x5+5x6+.+99x100 巧算：1x2+2x3+3x4+4x5+5x6+6x7...+8x9 1x3+2x4+3x5+4x6..+99x101=? 1/1x2+2/1x3+3/1x4+4/1x5+5/1x6+6/1x7= 1/2x4+1/3x5+1/4x6+1/5x7+...+1/97x99=?RT 1x2+2x3+3x4+4x5+5x6+6x7+7x8+8x9+9x10+10x11 (2X2)/1X3+(4X4)/(3X5)+(6X6)/(5X7)+...+(20X20)/(19X21)==? 1x2+2x3+3x4+4x5+5x6+6x7+7x8+8x9= 1x2+2x3+3x4+4x5+5x6+6x7+7x8+8x9+9x10+10x11+ +nx(n+1)= 帮我用lingo或者lindo算个题呗?x1+x4+x5+x6+x7>20x1+x2+x5+x6+x7>13x1+x2+x3+x6+x7>10x1+x2+x3+x4+x7>12x1+x2+x3+x4+x5+>16x2+x3+x4+x5+x6+>18x3+x4+x5+x6+x7>20格式不对也改下哈,>在lingo中应该和>=一样吧?min=(5x1+4x2+3x3+3x4+3x5+3x6+4x7) 1x5+2x5+3x5+4x5+5x5… 麻烦给我一个公式. 1/1x3+1/2x4+1/3x5+1/4x6+1/5x7+1/6x8 1/1x2+1/2x3+1/3x4+1/4x5+1/5x6+......1/2008x2009 1/2x4+1/3x5+1/4x6+1/5x7+.1/8x10+1/9x11