7x-x^2≥0解集是

7x-x^2≥0解集是 3≤|8-x| |x+1|>2-x |x+3|7|x+1| x^2-6|x|+9>0 |x-1|+|x+2|≥5 （1）方法 f(x)分段函数-x^2+x(x≥0),x^2+x(x *-----------------------------------------------*| 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 || X²-4X+1/3X²-7X+2≥1 （x-1)-(-2x-3)(3x-1)＞0 x²-4x+1/3X²-7X+ 2≥1 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 已知1+x+x^2+x^3=0,求x+x^2+x^3+x^4+x^+x^6+x^7+x^8的值 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-2)(x-3)/(x+5)(x-7)＞0(x-2)(x-3)(x+2)(x+3)＞0 不等式x^2-2x+丨x丨/x≥0的解集是 y=x^2-2x (x≥0) -x^2-2x(x 求y=(x^2)+2x(x≥0) y=-x+2x(x 已知函数f(x)=x²+x+1,x≥0；2x+1,x 已知f(x)={x²+x+1,x≥0 2x+1,x 函数f(x)={2x,x≥0 {x(x+1),x 已知f(x){x/2,x≥0;-x²+3x,x f(x)是奇函数,x≥0时,f(x)=x+x^2,求x 若函数f(x)=｛x²+2x(x≥0) g(x)(x