x>0,y>0,試證x/y y/x>=2

x-y/x-x+y/y-(x+y)(x-y)/y²y/x=2x-y/x-x+y/y-(x+y)(x-y)/y²y/x=2x-y/x-x+y/y-(x+y)(x-y)/y²

（x+y-5)*（x+y-5)+（x-y+3)=0x*x-y*y（x+y-5)*（x+y-5)+（x-y+3)=0x*x-y*y（x+y-5)*（x+y-5)+（x-y+3)=0x*x-y*y这是什么

已知:3x-5y=0,求x/y,x-y/y,x-y/x已知:3x-5y=0,求x/y,x-y/y,x-y/x已知:3x-5y=0,求x/y,x-y/y,x-y/x3x-5y=03x=5y→x/y=5/

(X,Y)f(x,y)={12y^2,0(X,Y)f(x,y)={12y^2,0(X,Y)f(x,y)={12y^2,0同学,我能写的就是这么多了.

已知x>0,Y>0,如何证x^2/y+y^2/x>=x+y已知x>0,Y>0,如何证x^2/y+y^2/x>=x+y已知x>0,Y>0,如何证x^2/y+y^2/x>=x+y我打算用分析法,那么倒着画

x*x+2x+y*y-4y+5=0x=y=x*x+2x+y*y-4y+5=0x=y=x*x+2x+y*y-4y+5=0x=y=x^2+2x+y^2-4y+5=0x^2+2x+1+y^2-4y+4=0(

设Z=X+Y,其中X,Y满足X+2Y>=0,X-Y设Z=X+Y,其中X,Y满足X+2Y>=0,X-Y设Z=X+Y,其中X,Y满足X+2Y>=0,X-Y（线性规划）由条件当X=Y=3时有最大值Z=6即得

已知x*x-4xy+4y*y=0求[2x(x+y)-y(x+y)]/(4x*x-4xy+y*y)的值?已知x*x-4xy+4y*y=0求[2x(x+y)-y(x+y)]/(4x*x-4xy+y*y)的

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)的值若(x*x+y*y)(x*x+y*y)-4x*x*y*y=0,求代数式(

已知x*x+4x+y*y-2y+5=0,则x*x+y*y=?已知x*x+4x+y*y-2y+5=0,则x*x+y*y=?已知x*x+4x+y*y-2y+5=0,则x*x+y*y=?X^2表示平方X^2

已知X*X+Y*Y+6X-8Y+25=0求（Y/X)+(X/Y)-2=?已知X*X+Y*Y+6X-8Y+25=0求（Y/X)+(X/Y)-2=?已知X*X+Y*Y+6X-8Y+25=0求（Y/X)+(

不等式证明猜想(X^y+Y^y)^x>(Y^x+X^x)^y(x>y>0)不等式证明猜想(X^y+Y^y)^x>(Y^x+X^x)^y(x>y>0)不等式证明猜想(X^y+Y^y)^x>(Y^x+X^

x*x+2x-y*y+6y-8=0,x+y不等于2,求x-y的值x*x+2x-y*y+6y-8=0,x+y不等于2,求x-y的值x*x+2x-y*y+6y-8=0,x+y不等于2,求x-y的值x

设x大于1,y大于0,x^y+x^-y=2根号二,x^y-x^-y等于?设x大于1,y大于0,x^y+x^-y=2根号二,x^y-x^-y等于?设x大于1,y大于0,x^y+x^-y=2根号二,x^y

变量x,y满足x-2y=0,x变量x,y满足x-2y=0,x变量x,y满足x-2y=0,x令a=2x-y,b=x+y用ab表示不等式,有4/3a-2/3b=01/3(a+b)

7y(x-3y)-2(3y-x)=0.x=?,y=?7y(x-3y)-2(3y-x)=0.x=?,y=?7y(x-3y)-2(3y-x)=0.x=?,y=?7y(x-3y)-2(3y-x)=07y(x

mathematica软件,已知y[x],Y=f1(x),X(x)=f2(x),如何plotY[X]?y[x_]:=x+9.81/2*x*xk=1X[x]=x-k*y''[x]/(1+(y''[x])^2

先化简,再求值[2/3x-2/x+y（x+y/3x-x-y）]*x/x-y,其中5x+3y=0先化简,再求值[2/3x-2/x+y（x+y/3x-x-y）]*x/x-y,其中5x+3y=0先化简,再求

先化简,再求值:[3x-2/x+y(x+y/3x-x-y)]/(x-y/x),其中5x+3y=0先化简,再求值:[3x-2/x+y(x+y/3x-x-y)]/(x-y/x),其中5x+3y=0先化简,

Y=X^2X(X>0)求导Y=X^2X(X>0)求d(Y)/d(X)Y=X^2X(X>0)求导Y=X^2X(X>0)求d(Y)/d(X)Y=X^2X(X>0)求导Y=X^2X(X>0)求d(Y)/d(