x*y''+x﹡(y')^2-y'=0微分方程通解

x-y/x-x+y/y-(x+y)(x-y)/y² y/x=2 (X,Y) f(x,y)={12y^2,0 已知x>0,Y>0,如何证x^2/y+y^2/x>=x+y x*x+2x+y*y-4y+5=0 x= y= 设Z=X+Y,其中X,Y满足X+2Y>=0,X-Y 已知x*x-4xy+4y*y=0 求[2x(x+y)-y(x+y)]/(4x*x-4xy+y*y)的值? 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*y)的值 y+y'-2y=2x 微分方程y - 2y' + y = x 已知x*x+4x+y*y-2y+5=0,则x*x+y*y=? 已知X*X+Y*Y+6X-8Y+25=0 求（Y/X)+(X/Y)-2=? x*x+2x-y*y+6y-8=0,x+y不等于2,求x-y的值 设x大于1,y大于0,x^y+x^-y=2根号二,x^y-x^-y等于? （x+y-5)*（x+y-5)+（x-y+3)=0 x*x-y*y 已知:3x-5y=0,求x/y,x-y/y,x-y/x 7y(x-3y)-2(3y-x)=0 .x=?,y=? 变量x,y满足x-2y=0,x 填空：x-y/x+y=( )/x^2-y^2