（3y+2)（y-4)-3(y-2)（y-3)计算

计算:(-x-2y) * (3x-y) 计算(x+y)(x+y)^2(-x-y)^3 (x-3y)(y+2x)-(4y-3x)(3x+4y)计算 计算【3(x-y)^2(x+y)^-2/4(x+y)^2(x-y)^-2】^-2 计算(2y+1)^2×(2y+1)^3+(2y+1)^4【-(2y+1)】 计算（2x-3y)(x+4y)-(3x+y)(x-2y) 计算:[(2x - 3y)^2 - (x-y)(4x+2y)] / 2y 计算(x^8-x^7y+x^5y^3-x^4y^4+x^3y^5-x^y^7+y^8)(x^2+xy+y^2) 计算:1/(x-y)-1/(x+y)-2y/(x^2+y^2)-4y^3/(x^4+y^4)-8x^7/(x^8+y^8 计算：3x-2y- [-4x+(z+3y)] 计算（4x^2y-9y)/(2x+3) 计算(3x+y-2)(4x-y+2)