【{x²-4x+4/x²-4}-x/x+2】÷x-1/x+2

(x+1-1/1-x)÷(x-x²/x-1) (x-4/x-x-6+ x+2/x-3)÷x+1/x-3 [（x+2）/(x²+2x)-(x-1)/(x²-4x+4)]÷(x-4)/x 计算:2x/(x-2)(x+1)÷(1－x/x+1)-x²+2x/x²-4? (4x³)²×[x³-x(2x-1)] 化简{x²-2x分之x+2-x²-4x+4x分之x-1}除以X分之(x-1)(X-4)乘以（2-x） (2x-6)/(x²-4x+4)÷(3-x)/(x²+6x+9)×(2-x)/(x+3) 3x⁷*x⁴+2x*x²*x⁴-4x⁵*(-x)² x(2-1/x)+x/(x^2-2x)÷(3-x)/(x^2-4) (x+1)/(x²+3x+2)+(x²-2x)/(x²-4) x²-2x分之x+2-x²-4x+4分之x-1 x+2/x²-2x-x-1/x²-4x+4计算 解方程(x²-x+4)x-(x-1)(x²+2)=x+7