作业帮24x²y² 3xy
来源：学生作业帮助网 编辑：作业帮 时间：2024/05/16 14:41:40
：(2x-y)(x^2+xy-2y^2)=（2x-y）（x+2y)(x-y)xy(x^2-xy)(-3xy^2)=xy*x(x-y)*(-3xy^2)=-3x^3y^3(x-y)
解题思路：提取公因式进行分解解题过程：附件最终答案：略
原式=x²-y²-(4x²y²+12xy²+9y²)=x²-y²-4x²y²-12xy²-
xy(xy+1)+(xy+3)-2(x+y+1/2)-(x+y-1)^2=xy(xy+1)+(xy+1)+2-2(x+y)-1-[(x+y)^2-2(x+y)+1]=(xy+1)^2+2-2(x+y)
3xy是3x原式=(x-3y)(x+2y)+3x+y+2十字相乘x-3y2×x+2y1所以原式=(x-3y+2)(x+2y+1)
解题思路：本题主要利用完全平方公式进行因式分解即可求出结果解题过程：解:x²－6xy＋9y²=(x-3y)2
3xy[2xy-x(y-2)+x-1]=3xy(2xy-xy+2x+x-1)=3xy(xy+3x-1)=3x^2y^2+9x^2y-3xy
3xy[2xy-x（y-2）+x]＝3xy[2xy-xy+2x+x]=3xy(xy+3x)=3x²y²+9x²y
(3xy)平方/(-xy)+(x-2y)平方-(x+2y)(x-2y)=-9xy+(x-2y)(x-2y-x-2y)=-9xy+(x-2y)(-4y)=-9xy-4xy+8y²=8y
(-3x^y+2xy)-(4x^+xy)=-3x^y+2xy-4x^-xy=-3x^y+xy-4x^所以填上-3x^y+xy-4x^
5x^2y/-1/2xy*3xy^2=-7.5x²y²
解题思路：将原方程右边分解因式为（x-4y)(x+y)=0,可得x=4y或x=-y,进而可求出x与y的比值。解题过程：解：∵x2-3xy-4y2=0∴（x-4y)(x+y)=0∴x=4y或x=-y∵x
x^3y(-4y)^2+(-7xy)^2*(-xy)-5xy^3*(-3x)^2=16x^3y^3-49x^3y^3-45^3y^3=-78x^3y^3如果本题有什么不明白可以追问,
原式(-xy/3)²*[xy(2x-y)-2x(xy-y²)]=(x²y²/9)(2x²y-xy²-2x²y+2xy²)
2(x+xy)-[(xy-3y)-x]-(-xy)=2x+2xy-xy+3y+x+xy=3x+3y+2xy=3（x+y）+2xy=3*（-2）+2*3=0
∵x-y=4xy，∴2x+3xy-2yx-2xy-y=2(x-y)+3xyx-y-2xy=8xy+3xy4xy-2xy=112．故答案为：112．
[(x-y)/(x+3y)]/[(x^2-y^2)/(x^2+6xy+9y^2)]-xy/(x+y)=(x-y)/(x+3y)*(x+3y)^2/(x-y)(x+y)-xy/(x+y)=(x+3y)/
解题思路：结合完全平方公式进行求解解题过程：答案见附件最终答案：略
1、(-7x^y)(2x^y-3xy^3+xy)=-14x^(2y)+21x^(y+1)y^3-7x^(y+1)y;2、((x-y)^6)/((y-x)^3)/(x-y)=-(x-y)^3/(x-y)
原式=-x²y+2xy²+2x²y²-4xy³-3x³+27x³y-18x²y²+2x²y-18x&