1×3/x +3×5/x +5×7/x+..2007×2009/x=2008的解

来源:学生作业帮助网 编辑:作业帮 时间:2024/04/16 18:16:30
1×3/x +3×5/x +5×7/x+..2007×2009/x=2008的解

1×3/x +3×5/x +5×7/x+..2007×2009/x=2008的解
1×3/x +3×5/x +5×7/x+..2007×2009/x=2008的解

1×3/x +3×5/x +5×7/x+..2007×2009/x=2008的解
x/1*3+x/3*5+x/5*7+.+x/2007*2009=2008
x(1/1*3+1/3*5+1/5*7+.+1/2007*2009)=2008
x[1/2*(1-1/3)+1/2*(1/3-1/5)+1/2*(1/5-1/7)+.+1/2*(1/2007-1/2009)]=2008
x/2(1-1/3+1/3-1/5+1/5-1/7+.+1/2007-1/2009)=2008
x/2(1-1/2009)=2008
x/2*2008/2009=2008
x/2*1/2009=1
x=2*2009
x=4018

*-----------------------------------------------*| 6 4 X | 8 X X | X X 5 || X X X | X X X | X 7 8 || X X X | X X X | X X X ||---------------+---------------+--------------- || X X X | X X X | 5 1 X || X X X | X 6 X | X X X || 8 X X | 3 5 X | 2 X X || 填九宫格帮帮忙.x x 6 x x 7 x x 98 x x x 3 x 1 x x 9 x x 6 x 5 x 3 x x x 3 x x x x 1 8x x x 9 x 1 x x x2 1 x x x x 6 x x x 6 x 7 x 3 x x 1 x x 9 x 2 x x x 47 x x 8 x x 5 x x 求一个数独答案X X X 9 X X X 8 2 X 6 3 X X 1 4 X 99 X 8 X X X X X XX X X 6 7 X 3 X XX 4 6 X 5 X 2 9 XX X 7 X 2 3 X X XX X X X X X 7 X 17 X 4 3 X X 6 2 X6 3 X X X 7 X X X 难倒爱因斯坦的九宫格X 7 X | X 8 1 | X X X |X X X | X 4 X | 7 5 9 |X X 5 | 7 X 9 | X 1 4 |5 X X | X X 8 | 3 9 X |3 9 6 | 4 X 7 | X X 2 |X 8 7 | 9 X X | X X X |4 X X | 6 X 5 | X X X | X X 4 | X X 1 |2 X X | X X X | X X X | X 3 X | X X X |X 6 如下9*9宫图如何填x x x 1 x x x 2 9x x 5 x x x x x 4x 6 8 x x x x x xx x x 7 x x 5 x xx 2 x x 6 x x 8 xx x 3 x x 9 x x xx x x x 5 x 1 6 x 4 x x x 3 x x x x 7 x x x x 2 x x x 用递归法求y=x-(x*x*x/3!)+(x*x*x*x*x/5!)-(x*x*x*x*x*x*x/7!)+. 解九宫格题目(X为未知数)9 X 2 X 7 X 8 X XX X 4 X X 9 X 6 X1 3 X 5 X X X X 24 X X 8 5 X X 1 XX 8 9 4 X 1 6 7 XX 1 X X 3 6 X X 88 X X X X 2 X 3 6X 5 X 6 X X 9 X XX X 7 X 4 X 2 X 1 已知3x*x-x=1,求6x*x*x+7x*x-5x+2000 x+2/x+1-x+4/x+3=x+6/x+5-x+8/x+7 x=? [(x+2)/(x+3)-(x+1)/(x+2)+(x+4)/(x+5)-(x+3)/(x+4)]/[(x的平方+7x+13)/(x的平方+8x+15)] 计算:[(x+2)/(x+3) - (x+1)/(x+2) + (x+4)/(x+5) - (x+3)/(x+4) / (x^2 + 7x + 13)/(x^2 + 8x + 15) 解决数独问题x 1 x 7 x x x 3 xx x x x 4 x 2 x x9 x 3 6 x 8 7 x 58 x x x x 9 x x xx x 2 x 5 x x x 4x 3 x x x x 6 x xx x x x x x x x 26 x x x x x x x 7x 5 4 1 7 x 9 8 x这道题我用了很多办法都没有头绪,请帮忙的朋友把解题的思 x+2/x+1-x+3/x+2-x+4/x+3+x+5/x+4 因式分解(x+1)(x+3)(x+5)(x+7)-12 因式分解 (x+1)(x+3)(x+5)(x+7)+15 (x+1)(x+3)(x+5)(x+7)+15因式分解 (x-1)(x-3)(x-5)(x-7)-84因式分解 (x-7)(x+3)+(x-1)(x+5)=102