(3/4x^2y^3+6/5x^3y^4-9/10x^4y)除以3/5x^2y.3a^2(2a^2n+1+3a^2n+5a^2n-1)除以(-a)^2n-1.如果单项式-3x^2a-by^2与1/3x^3a+by^5a-8是同类项,求这个单项式的积.（2.4*10^4）^2除以(3*10^3)用句号隔开了，

因式分解(x-2y)(x-3y)+(x-4y)(x-5y)+（x-3y)(x-5y)+(x-2y)(x-4y) 因式分解 x-xy+3y-3x 2x+xy-y-4x+5y-6 【(4x-3y)(4x+3y)-(2x-3y)(5x+3y)]除以6x 5/4(x+y)(-x-y)^3*[-4/3(x-y)]*[-3/5(y-x)^2] (3x-4y)(5x-4y)-(7x-8y)(6y-5x) 化简(x+y)-(2x+y/2)-(3x+y/6)-(4x+y/12)-(5x+y/20)-……-(10x+y/90) 5x^3y(x-y)^3-10x^4y^3(y-x)^2因式分解 5x^3y(x-y)^3-10x^4y^3(y-x)^2 x+y/2+x-y/3=6,4(x+y)-3(x-y)=-20 {(x+y)/2+(x-y)/3=6 4(x+y)-3(x-y)=-20 4(x+y)-3(x-y)=-20,2/x+y+3/x-y=6 {3(x+y)-4(x-y)=4 {x+y/2 + x-y/6=1 81/8*(-x-y)^6*(x-y)^3*4/9(x+y)^4*(y-x)^2 5X^3Y(X-Y)-10X^4Y^3(Y-X)^2因式分解 （x+y）^6/(x+y)^4-(x-y)^5/(x-y)^3 化简 .. 4x-3y/x-2y÷6y-8x/y-2x （x+y）/2- x-y/2=6 3(x+y)=4(x-y) x+y/3+x-y/2=6 4(x+y)-2(x-y)=40