x²y-xy² x²-y²,其中x y=1 2-根3-搜答案-搜搜考试网

(x-2)²+∣y-3∣=0(x-2)²=0,∣y-3∣=0x=2y=3(x-y)/(x²-2xy+y²)-(xy+y²)/(x²-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

xy^3÷(-xy)+(x+2y)(x-2y)=-y^2+x^2-4y^2=x^2-5y^2=2-5=-3再问：不好意思啊！题目......再答：题目怎么了，不影响结果啊。平方还是正的

原式=(x-y)(x²+2xy+y²-xy)-(x-y)(x²-2xy+y²+xy)=(x-y)(x²+xy+y²)-(x+y)(x&sup

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

xy-1+x-y

xy-1+x-y=XY+X-Y-1(加法交换律）=（XY+X）－（Y＋1）＝X（Y＋1）－(Y+1)（提取公因式X）=(Y+1)(X-1)（提取公因式Y+1）这样可以么?

（x-y）[(x+y)(x+y)-xy]+(x+y)[(x-y)(x-y)+xy]=(x-y)(x+y)^2-（x-y)xy+(x+y)(x-y)^2+(x+y)xy=(x-y)(x+y)(x+y+x

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

解题思路：根据题意，由完全平方公式的知识可求解题过程：varSWOC={};SWOC.tip=false;try{SWOCX2.OpenFile("http://dayi.prcedu.com/inc

3(2x^2y-3xy^2)-(xy^2-3x^2y)=6x²y-9xy^2-xy²+3x²y=9x²y-10xy²=9*1/4*(-1)-10*(1

原式=(x-y)²/(x+y)²(x+y)^4/(x-y)²*1/(x+y)=x+y=-3

（x+2y-3xy)-(-2x-y+xy)=x+2y-3xy+2x+y-xy=(1+2)x+(2+1)y-(3+1)xy=3x+3y-4xy=3(x+y)-4xy=3*1/2-4*(-1/2)=3/2

(x+y)²-(x-y)(x+y)-(xy)²÷(xy)=x²+y²+2xy-(x²-y²)-xy=2y²+xy.方程组｛3x+2

解题思路：：∵x+y=0,x+13y=1，解得x=1/12,y=-1/12∴x²+12xy+13y²=1/144-1/12+13/144=14/144-1/12=2/144=1/72解题过程：已知x+

（x+2y-3xy)-(-2x-y+xy)=x+2y-3xy+2x+y-xy=(1+2)x+(2+1)y-(3+1)xy=3x+3y-4xy=3(x+y)-4xy=3*1/2-4*(-1/2)=3/2

（x+2y-xy)-(-2x-y+xy)=x+2y-xy+2x+y-xy=3x+3y-2xy=3(x+y)-2xy=3×0.5-2×(-0.5)=1.5+1=2.5

3x-4xy+3y再问：然后的过程再答：再带入值等于3.5再答：马上再答：给你照片再答：再答：亲采纳哟

x²+xy/(x-4y)(x+y)=x(x+y)/(x-4y)(x+y)=x/(x-4y)=4/(4+4)=1/2

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

原式=(x+y)(x-y-x+2y)/y=(x+y)y/y=x+y因为已知代数式无意义,即：0的0次方无意义,所以3x-2y-7=0及2x+3y+4=0,解得：x=1,y=-2代入x+y=-1