f(x+y,xy)=x^2+y^2
f(x+y,xy)=x^2+y^2
设f(x+y,xy)=x^2+y^2,则f(x,y)
高数题 设f(x+y,x-y)=x^2-xy,则f(x,y)=多少
已知二元函数f(xy,x+y)=x^2+y^2,求f(x,y)
f(2x+y,2y+x)=xy,求f(x,y)
高数题!f(x,y)=x^3-2xy+3y^2,求f(x+y,x-y).
f(x+y,x-y)=2x②+5xy+2y②+6求f(x,y)
对任意的实数x,y,f(x+y)=2f(y)+x^2+2xy-y^2+3x-3y,求f(x)
f(x)满足f(x+y)+f(xy)=2f(x)f(y)求函数的奇偶性
f(x)对于任意实数xy总有f(x+y)+f(x-y)=2f(x)f(y)成立,求证f(x)为偶函数
函数y=f(x)对任意实数x,y都有f(x+y)=f(x)+f(y)+2xy 求f(0)的值
f(x+y,xy)=x²+y²,则f﹙x,y﹚=?函数z=2xy-3x²-3y²