6x^4y^3+12x^3y^4-24x^2y^5
6x^4y^3+12x^3y^4-24x^2y^5
x^8-x^7y+x^6y^2-x^5y^3+x^4y^4-x^3y^5+x^2y^-xy^7+y^8
化简(x+y)-(2x+y/2)-(3x+y/6)-(4x+y/12)-(5x+y/20)-……-(10x+y/90)
5/12[-4/3(x-y)^3] *(x+y)^2 * (-x-y)^3 * 5/6(y-x)^2
解方程组:x+y/2+x-y/3=6 4(x+y)-5(x-y)=12
化简求值:(x+y)-(2x+1/2y)-(3x+1/6y)-(4x+1/12y)-(5x+1/20y)-.(10x+1
(3x-4y)(5x-4y)-(7x-8y)(6y-5x)
(x+2)(x+3) (x-4)(x+1) (y+4)(y-2) (y-5)(y-3)
{3(x+y)-4(x-y)=4 {x+y/2 + x-y/6=1
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