如果9x^2-(4a+3b)xy-(a+2b)y^2=(3x-y)^2,求a^3-4a^2b+4ab^2
x²(x+y)(y-x)-xy(x+y)(x-y) 已知a+b=4,ab=-2,求多项式3a²b+3
3a-3b/10ab*25a^b3/a^-b^= x^-4y^/x^+2xy+y^/x+2y/2x^+2xy
已知:A=X*X-3xy+y*y,B=2x*x+xy-3y*3y.求A+B,A-B,A+2B
已知A=4X平方减4XY+Y平方,B=x平方+XY减5Y平方 求(3A-2B)-(2A+B)
已知A=4x²-4xy+y²,B=x²+xy-5y²,求:⑴A-3B;⑵2A+B
设A=2x-3xy+y+x-3y,B=4x-6xy+2y+4x-y,若|x-3a|+(y+3)=0,且B-2A=a.求A
已知2x²+xy=a,3y²+2xy=b,求4x²+8xy+9y²的值(用a,b
已知A=2x^2-4xy+6y^2+3x-y,B=x^2-2xy+3y^2-2x+y,如果A-2B=3a,并且|x-a|
几道因式分解..4ab(a+b)^2-6a^2b(a+b)(x+y)^2(x-y)+(x+y)(x-y)^22a(a-3
分解因式1.2a(x-y)-3b(y-x)2.-x^y-2xy+35y3.a^(x-y)-4b^(x-y)若|a+2|+
已知A=x²-2xy+y,B=x²+2xy+y²-3,求2A-[B-(B-A)+2A+B]
设A=2x^2-3xy+y^2-x+2y,B=4x^2-6xy+2y^2-3x-y.求B-2A;若|x-2a|+(y+3