-1\3x^2y^m+1+x^2y-3x^4-5是五次四项式,单项式9\5a^3n b^3-m c-1\3x^2y^m+1+x^2y-3x^4-5是五次四项式，单项式9\5a^3n b^3-m c的次数与多项式的次数相同，则n=？

(Y-X)^3*(X-Y)^m+(X-Y) ^m+1*(Y-X)^2 (x-2y)^m+1/(x-2y)^m-3/(2y-x)^3怎么算 计算：2/1-m-1/m-1.2x/x-y -y/y-x -y-2x/x-y.12/m²-9 -2/m-3 分解因式x^m+3-2x^m+2y+x^m+1y^2 分解因式：x^m+3-2x^m+2*y+x^m+1*y^2 分解因式x^m+3-（2x^m+2）y+（x^m+1)y^2 计算题:9(x-y)^3[-1/9(x-y)^m+5](y-x)^2 计算:(1).(2x-3y)/(y-x)-(x+2y)/(x-y) (2).[5m/(m-3)+2m/(m+3)]*(m^2-9)/m 已知M={(x,y)|y=-x^2+mx-1},N={(x,y)|y=-x+3,0 计算：(y-x)^3(x-y)^m-(x-y)^m+2(y-x) X^3*y^(m-1)*x^(m+y)*y^(2n+2)=x^9y^9 x²/xy-x/y 3x/4x+y - x-2y/4x+y (1-y/y+x)÷x/y²-x² 3（x-1)³y-（1-x）³z m(x-y)²-x+y x²(x+y)(y-x)-xy(x+y)(x-y) 因式分解 数学计算填空(5x+y)(5x-y)(5x+y)(-5x+y)(5x+y)(-5x-y)(5x+y)(x-5y)(x ^m+y ^n) （y ^n- x^ m)(x ^m+2y-3x^3)²(x-2y）(______)=4y²-x²(__________)²=m²-2m+1（只需要写一个代数式）(__________+3)²=4x²+(_______) 若2/x-1/y=3,求[y/x-y/x-y(x-y/x-x+y)]/x-2y/x的值 填空：1.（1）2m（y-x）^2=（ )(x-y)^2填空：1.（1）2m（y-x）^2=（ )(x-y)^2（2）-2m(y-x)^3=( )(x-y)^3( 3 ) (x+y)(y-x)=-(x+y)( )( 4 ) -m(y-x^2)=m( ) 求关于x,y的二元一次方程组2(x+1)+y=m+3 x-2y=3m-2的解x,y满足x 4m(x-y)-2m^2(y-x)^3