4x²-(4x²-4xy+y²)
(-x-2y)(x²-2xy+4y²)
3x²y+xy²-[2xy²-4x²y+(x²y-2xy²)
化简(x²y-4y²)/(x²+4xy+4y²)*[(4xy)/(x-2y)+x
(2x²y-3xy²)-3(x²y-2xy²)+2(x²y-4xy
因式分解:x²-y²+4xy
因式分解:4x²y+4xy²+xy²
x²+xy/(x-4y)(x+y),其中x=4,y=-1
已知x²+y²-8x+6y+25=0,求(x-y+4xy/x-y)(x+y-4xy/x+y)
-3(xy-2x²)-[y²-(5xy-4x²)+2xy]
1.化简:x²-4y²/x²+y²+2xy÷2y+x/x²+xy.
x²+y²+2xy分之x²-4y² ÷x²+xy分之2y+x
(x²+2xy+y²分之x²-4y²)÷(x²+xy分之x+2y)