已知a=2x²-3xy+y²,b=x²+2xy-3y²,化简:(1)a+b (2
已知a=2x²-3xy+y²,b=x²+2xy-3y²,化简:(1)a+b (2
已知A=4x²-5xy+y²,B=x²+3xy-5y² 求:A-2B的值
设A=2x²-3xy+y²-x+2y,B=4x²-6xy+2y²+3x-y.若x
设A=2x²-3xy+y²-x+2y,B=4x²-6xy+2y²-3x-y,若|
设A=2x²-3xy+y²-x+2y ,B=4x²-6xy+2y²+3x-y .
已知x/y=3,求x²+2xy-3y²/x²-2xy+y²
已知x/y=3,求x²+2xy-3y²/x²-xy+y²的值
计算:(1).(-2xy²)*(3x²y)²
3y/2x+2y+2xy/x²+xy 2x/x²-64y²-1/x-8y (1/a+1/b
已知X²-5XY+6Y²=0,求(X²+3XY)\2Y²的值
已知多项式A=x²+2y²-z²,B=-4x²+3y²+2z²
已知A=2x²y-xy²,B=x²y-3xy²,且3A-2B-C=0,求C的表达