x^2-xy-2y^2=0是怎么变成(x+y)(x-2y)=0求解,
已知3x*+xy-2y*=0,求(x/y)-(y/x)-(x*+y*)/(xy)的值.*是平方
已知x*x-4xy+4y*y=0 求[2x(x+y)-y(x+y)]/(4x*x-4xy+y*y)的值?
求解微分方程(xy^2+x)dx+(y-x^2y)dy=0,y(2)=1的通解
求解一个微分方程:(2x·y^2-y)dx+(y^2+xy)dy = 0
【【求解微分方程】】xy'+y=x^2+3x+2
若(x*x+y*y)(x*x+y*y)-4x*x*y*y=0,求代数式(x*x+5xy+y*y)/(x*x+2xy+y*
已知3x^2+xy-2y^2=0,求{(x+y)/(x-y)+4xy/(y^2-x^2)}/{(x+3y)*(x-y)}
{x,xy,lg(xy)}={0,|x|,y} 则log8(X^2+Y^2)
求解微积分方程3道!1.(x^2+1)y'=xy求解微积分方程 2.y''+8y'+41y=0求解微积分方程 3.y''
已知x^2+xy-2y^2=0 (x不等于0,y不等于0),求x/y-y/x-(x^2+y^2)/xy的值
2x²-3xy=y²=0(x,y不得o)求x/y+y/x
已知(x+2)^2+|x+y+5|=0,求3x^2y-[2x^2y-(2xy-x^2y)-4x^2]-xy