圆x^2+y^2+2x+2y+F=0与直线2x+2y+F=0的位置关系是

(X,Y) f(x,y)={12y^2,0 圆x^2+y^2-4x-6y+F=0与y轴相切,则F= 已知函数F(X)对任意实数X,Y都有F(X+Y)=F(X)+F(Y),且当X大与于0时,F(X)大于0,F(-1)=-2,求F(X)在[-2,1]上的值域.已知三点A(A,2) B(5,1) C(-4,2A)在同一条直线上 ,则A=? y=e^x y'=e^x 可以写成 y=f(x)与导数y=f'(x) y=x^2 y=2x 写成y=f(x)与导数y=f'(x) y=f(-x+2)与y=f(x-2)关于y轴对称为什么不对? f(x+y)=f(x)+f(y)+2xy 若x-3y=0,且x≠0,2x+5y/3x-y的直是? f(x+y,x-y)=(x^2-y^2)/2xy,求f(x,y)! 设f(x+y,x-y)=x^2-y^2,则f(x,y)= 若f(x+y,y/x)=x^2-y^2,则F(X,Y)= 已知f(x+y,y/x)=x^2-y^2,则f(x,y)= f(x+y,y/x)=x^2-y^2求f(x,y) f(x+y,y/x)=x^2-y^2,求f(x,y),详见里面 f(x+y,x-y)=2xy(x-y),求f(x,y) f(xy,x-y)=x^2+y^2+xy;f(x,y)/∂x;f(x,y)/∂y 函数f(x,y)=xy/x*2 y*2,求limf(x,y)与limf(x,y) 已知f(0)=1,f(x-y)=f(x)-y(2x-y+1),求f(x) 已知：f(x+y)+f(x-y)=2f(x)*f(y),x.y取任何实数且f(0)不等于0,求证：f(x)为偶函数