计算:(2x-1)(2x+1)(x^2+1) 计算:(2x+y)(2x-y)+(x+y)2-2(2x2-xy)
计算:1/(2x) - 1/(x+y)((x+y)/(2x) - x - y)
计算:3xy[2xy-x(y-2)+x]
计算(1)x/x+y-x/x-y (2)a+2+4/a+2 (3)x^2-y^2/xy÷(x+y)
(x^2+xy/x-y)/(xy/x-y)计算
计算(3x^3y-x^2y+1/2xy)÷(-1/2xy)
计算3x[xy-2x(1/y-x/3]+3y(x²-y²)
计算3xy[2xy-x(y-2)+x-1]
计算4xy+(x-2y)的平方+(x+3y)(3y-x)
计算(1)3x/8y×16y²/27x² (2)(2xy-x²)÷x-2y/xy 2x-6
计算(2x)^-4+(4x^2)^-2 xy(x^-1+y^-1)
计算:(x+y/x-y)÷(xy+x^2)
通分计算:(1)2x-3/(x-1)(x-4) - x-2/(1-x)(4-x) (2)x平方-y平方/xy - xy-