帮我把下面这几道初二计算题算出来,一定要有过程 .有急用.(x+1)(x2-x+1); (x-y)(x2-xy+y2);
帮我把下面这几道初二计算题算出来,一定要有过程 .有急用.(x+1)(x2-x+1); (x-y)(x2-xy+y2);
x(x-1)-(x2-y)=-3,求x2+y2-2xy的值
在x2+2xy-y2,-x2-y2+2xy,x2+xy+y2,4x2+1+4x中,能用完全平方公式分解因式的有( )个
已知x-y+1,X2+Y2=25 求(x+y)2和x2-xy+y2的值
先化简再求值2(x2-xy)-3(2x2-3xy)-2[x2-(2x2-xy+y2)],其中x=-1,y=-2.
已知x2-2xy=3y2且x,y为非零实数 求:(1)2x+y/x-2y (2)2x2-3y2+5xy/x2+xy+y2
先化简再求值:-(x2+y2)+[-3xy-(x2-y2)],其中x=-1,y=2.
我做对了吗.x2(x-y)+y2(y-x)= x2(x-y)-y2(x-y)=x2-y2=(x+y)(x-y)
已知x(x-1)-(x2-y)=-3,求x2+y2-2xy的值.
如果实数x,y满足x2+y2=1,则(1+xy)(1-xy)有( )
分解因式:(1)(x2+2x+3)(x2+2x+2)-30; (2)x2+2xy+y2-4x-4y-12;(3
阅读下面例题:把多项式x2-2xy+y2-2x+2y+1因式分解.