f(x)+f(y)=f(xy) f(2)=1证f(8)=3f(x)是定义在(o,正无穷)上的 增函数

f(x+y)=f(x)+f(y)+2xy f(x+y)+f(xy-1)=f(x)f(y)+2f(n)表达式 f(xy)=f(x)+f(y),证明f(x/y)=f(x)-f(y) f(xy)=f(x)+f(y),f(2)=1,f(3)=? f(xy)=f(x)+f(y)且f(8)=3则f(2)= f(xy)=f(x)+f(y),f(8)=3,则f(根2)等于 f(xy)=f(x)+f(y),f(8)=3,求f(√2), 已知f(x+y)=f(x)+f(y)+2xy,求f(0) 函数f(x)满足关系式f(xy)=f(x)+f(y)求f(1/3)+f(1/2)+f(1)+f(2)+f(3) 导数：f(x+y)=f(x)f(y),且f'(o)=1,求f'(x)f(x+y)=f(x)f(y),且f'(o)=1,求f'(x)f(x+y)=f(x)+f(y)+2xy,且f'(o)存在,求f'(x) f(1+x)=af(x),且f'(0)=b,求f'(1) f'(0)=1,f(x+y)=f(x)+f(y)+2xy,求f(x) f(x)满足f(x+y)+f(xy)=2f(x)f(y)求函数的奇偶性 f(xy)=f(x)+f(y)的单调性 任意正实数成立f(xy)=f(x)+f(y),f(2) f(xy)=f(x)+f(y),证明f(1/x)=-f(x) f(xy,x-y)=x^2+y^2+xy;f(x,y)/∂x;f(x,y)/∂y 函数fx满足关系f(xy)=f(x)+f(y) 求f(1/3)+f(1/2)+f(1)+f(2)+f(3) 已知f(xy)=f(x)+f(y),求证f(x/y)=f(x)-f(y)