(9/5X10/7-3/1)X5/6

(9/5X10/7-3/1)X5/6 1x2+2x3+3x4+4x5+5x6+6x7+7x8+8x9+9x10+10x11 7分之5x10分之7-3分之1)x5分之6 计算：1/1x2+1/2x3+1/3x4+1/4x5+1/5x6+1/6x7+1/7x8+1/8x9+1/9x10. 1x2+2x3+3x4+4x5+5x6+6x7+7x8+8x9+9x10+10x11+ +nx(n+1)= 1/2x4+1/3x5+1/4x6+1/5x7+.1/8x10+1/9x11 (1-1/2x4)x(1-3/3x5)x(1-5/4x6)x(1-7/5x7)x(1-9/6x8)x(1-11/7x9)x(1-13/8x10)x(1-15/9x11) 2x2/1x3+4x4/3x5+6x6/5x7+8x8/7x9+10x10/9x11+12x12/11x13 仔细看看 给50啊 1/1x2+1/2x3+1/3x4+1/4x5.1/9x10简算 1/2x3+1/3x4+1/4x5.+1/8x9+1/9x10 1/2x3+1/3x4+1/4x5.+1/9x10 化简：(1x3)分之一+(2x4)分之一+(3x5)分之一+...+(7x9)分之一+(8x10)分之一 1x5+2x5+3x5+4x5+5x5… 麻烦给我一个公式. mathematic 程序问题Min= X1+ X2+ X3+ X4+ X5+ X6+ X7+ X8+ X9+ X10+ X11;X1+1>=9;X2+1>=9;X3+2>=9;X4+2>=3;X5+1>=3;X6+2>=3;X7+1>=6;X8+2>=12;X9+2>=12;X10+1>=7; X11+1>=7; X1>=0;X2>=0;X3>=0;X4>=0;X5>=0;X6>=0;X7>=0;X8>=0;X9>=0;X10>=0;X11>=0; 递等式计算,能简算的要简算.（1）0.89X10.1,（2）4.56X5.6+5.6X5.44,（3）92.8÷8÷1.25 1.5X8.4+3X10分之3+25X10%= 4.5÷（24又7分之5-2.5%X800= 7.5X5分之4-5.5X80%+0.4= 帮我算下这道题等于多少100+10+4x20+50+25+25+300+20x25+50+25x5+50+5+25+330+30x10+35x5+50+35x10+40+7x40+50+6x50=?,帮我解下 (-1)+3+(-5)+7+(-9)+11……+(-2007)+2009(1/1X3)+(1/2X5)+.+(1/2003X2005)(1/1X4)+(1/4X7)+(1/7X10)+.(1/2002)X(1/2005)