5x²-(3y²+7xy)+(2y²-5x²),化简
化简(3X²-XY+Y²)-5(X²-XY+2Y²)
化简 (x+y)(x²-xy+y²) ; 3(2x-1)(x+6)-5(x-3)(x+6)
化简3/(x²+2xy+y²)-4/(x²-2xy+y²)+5/(x²
x-y/x²÷x²-2xy+y²/xy*(xy-x²)
(xy-2y)(xy+2y)-(x-y)²-x²y² 其中x=5/2 y=- 3/5 先化
计算:x²y-(2xy²-5x²y)+3xy²-y³
(-3xy)(5x²y)+6x平方(2/7xy²-2y²)
计算:(-7x²y)(2x²y-3xy³+xy)
3x²y+xy²-[2xy²-4x²y+(x²y-2xy²)
已知(x+3)+丨X-y+10丨=0 ,求5x²y-[2x²y-(3xy-xy²)-3x&
无论x,y取何值时,代数式:(x³+3x²y-5xy+6y³)+(y³+2xy&
化简:(x²+y²/x-y)-(2xy/x-y)