若0＜x＜5／2 求1／5-2x+2／x的最小值

若x^3+x^2+x+1=0,求代数式1+x+x^2+x^3+x^4+x^5+...+x^2006+x^2007的值 若x*x+x+1+0,求x^7+2x^6+x^5+x^4+x^3+x*x+1的值 求函数f(x)=(x+5)(x+2)/(x+1),(x＜-1)的最大值 如果1+x+x^2+x^3=0,求x+x^2+X^3+x^4+x^5+x^6+x^7+x^8的值, x(x+1)+(x+2)+(x+3)+(x+4)+(x+5) = 27求x 若x^2-5x-1999=0,求[(x-2)^4+(x-1)^2-2]/[(x-1)(x-2)]若x^2-5x-1999=0,求[(x-2)^4+(x-1)^2-1]/[(x-1)(x-2)] 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 若0＜x＜5／2 求1／5-2x+2／x的最小值 若 x^2-3x-1=0 求 2x^4-7x^3+5x^2-x+4 *-----------------------------------------------*| 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 || (x-2)(x-4)-(x-1)(x-5)求过程 已知实数x满足5x*x-3x-5=0,求代数式5x*x-2x-[1/5x*x-2x-5]的值. 已知实数x满足5x*x-3x-5=0,求代数式5x*x-2x-1/5x*x-2x-5的值. 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 数学f(x)=x(x+1)(x+2)(x+3)(x+4)(x+5),求f'(0)=? 若x＜0,求函数y=2x/x^2+x+1的最小值 (x+3)(2x+5)-(2x-1)(x-8)=0求x 若3x^2-x=1,求6x^3+7x-5x+2009