化简求值(选择题)⒈式子-3x^2·y-10x^3+3x^3+6x^3·y+3x^2·y-6x^2·y-6x^3·y+7
化简求值(选择题)⒈式子-3x^2·y-10x^3+3x^3+6x^3·y+3x^2·y-6x^2·y-6x^3·y+7
化简求值:(x+y)-(2x+1/2y)-(3x+1/6y)-(4x+1/12y)-(5x+1/20y)-.(10x+1
化简求值 -3(2x-y)-{7x-〔6x+2x-(10x-8y)〕-x-2(3x-4y)}
化简求值:(7x-2y)(3x-2y-1)-(4x+3y)(9x+6y),其中x=2,y=-1
化简下列各式,并求值:3(x-y)²-7(x-y)+8(x-y)²+6(x-y) 其中x=2,y
先化简,在求值:(x-y)²+(3x-2y)(2x+y)-x(6x-y)
因式分解3x^2(x-y)+6x(y-x)
现化简,再求值:(3x-y)(x+2y)-2(x-3y)·(x-4y),其中x=4,y=1.5
化简求值:(x+y)+(2x+1/2y)+(3x+1/6y)+.+(9x+1/72y) ,其中x=1,y=-9
求值(2x+y)(2x-y)+3(2x-y)^2+(-3x)(3x-4y)+(4x^5-6x^3)/2(-x)^3
先化简再求值(x-y)(x+y)-(x-2y) 的完全平方+x(3x-5y)-(x-y)(x-2y),其中x=1/2 y
2(y-x)的平方-7(x-y)+6(x-y)-3(y-x)的平方