1.(x-y)(x2+xy+y2) 2.求值x2(x-1)-x(x2+x-1),其中x=2分之一
先化简,再求值:(1)2x2-5x x2 4x,其中x=-3 (2)(3x2-xy-2y2)-2(x2 xy-2y2),
先化简再求值2(x2-xy)-3(2x2-3xy)-2[x2-(2x2-xy+y2)],其中x=-1,y=-2.
先化简再求值:-(x2+y2)+[-3xy-(x2-y2)],其中x=-1,y=2.
先化简,再求值:2x2+(-x2-2xy+2y2)-3(x2-xy+2y2),其中x=2,y=-12
x(x-1)-(x2-y)=-3,求x2-y2-2xy的值
x(x-1)-(x2-y)=-3,求x2+y2-2xy的值
已知x(x-1)-(x2-y)=-3,求x2+y2-2xy的值
先化简,后求值:5x2-(3y2+5x2)+(4y2+3xy),其中x=-1,y=13.
已知x-y+1,X2+Y2=25 求(x+y)2和x2-xy+y2的值
2x2+xy-3y2+x+4y-1因式分解
已知x2+4y2+x2y2-6xy+1=0,求 x4-y4/2x-y 乘 2xy-y2/xy-y2 除以(x2+y2/x
先化简,再求值:(x+2x2-2x-x-1x2-4x+4)÷x2-16x2+4x,其中x=2+3.