计算(1/2xy+y²+1)+(x²-1/2xy-2y²-1)
计算(1/2xy+y²+1)+(x²-1/2xy-2y²-1)
计算(1)3x/8y×16y²/27x² (2)(2xy-x²)÷x-2y/xy 2x-6
计算3x[xy-2x(1/y-x/3]+3y(x²-y²)
计算(3x^3y-x^2y+1/2xy)÷(-1/2xy)
计算3xy[2xy-x(y-2)+x-1]
因式分解xy²-2xy+x+2y-1
(1)-2分之1xy(3y²-2xy+3x²y)
(1/2x²y-2xy+y²)×3xy
合并同类项并计算 -3[y-(3x²-3xy)]-[y+2(4x²-4xy)]其中,x=3,y=1/
计算 2xy[4x²y²-3y(xy+x²y)-xy²]
计算2分之1xy²(-2xy)+3x²y的3次方=
计算;(xy-x²)÷x²-2xy+y²/xy · x-y/x²