2x²-9x+7>0
2x²-9x+7>0
(x+1)(x+2)(x+3)x+1=0则3x²+9x+7
不等式|(x+3)/x|>(x+3)/x,不等式(x²-9)/(x-2)>0
7x²-4x-3=0 -x²-x+12=0 x²-6x+9=0 (3x-2)²=
|X-1|+|X-2|+|X-3|+|X-4|+|X-5|+|X-6|+|X-7|+|X-8|+|X-9|+|X-10|
x+2x+3x+4x+5x+6x+7x+8x+9x=9x-8x-7x-6x-5x-4x-3x-2x-x.x等于多少?
解方程 x(x+1)-x-9=0 x²-2x=224 x(x-2)=2(2-x) x²-(2(√2)
解方程(3x^2+9x+7)/(x+1)-(2x^2+4x-3)/(x-1)-(x^3+x+1)/(x^2-1)=0
3≤|8-x| |x+1|>2-x |x+3|7|x+1| x^2-6|x|+9>0 |x-1|+|x+2|≥5
方程(x+1)(x+2)(x+3)(x+4)(x+5)(x+6)(x+7)(x^2+8x+9)+64=0
2x^6×x³-3x^9+5x²×x^7等于多少
因为x²-x+2=(x-1/2)²+7/4>0所以x(x²-x+2)