设f(x,y)=sin(xy),则fx(x,y)=?

设f(x,y)=sin(xy),则fx(x,y)=? f（x,y）=sin（xy）,求fx（x,y）=? 设y=f(e^sin^22x),其中fx可导.求y f(x+y)=fx+fy+xy+1,则f1=1,求fx 设函数fx对任意实数xy都有f（x+y）=fx+ fy且x>0时fx 设函数f（x,y)=sin(x+y),那么f(0,xy）=( ) 设函数f(x,y)=xy+y/x,则fx（1,1）=?(A) 0 (B) 1 (C) -1 (D) 2 设f(x-y,y/x)=xy,则f(xy,x+y)等于什么 设f(x-y,y/x)=xy,则f(xy,x+y)等于什么 F(x+y)=f(x)+f(y)+2xy f'(0)=2fx定义域为r,求fx f(xy,x-y)=x^2+y^2,则fx(x,y)+fy(x,y)= f(x,y)=xy^2+e^x,则fx(0,1)等于多少 设f(x+y,x-y)=xy,z=(xy,x/y),则dz= 设f(x+y,xy)=x²+y²+xy,则df(x,y)= 设Fx可导,求下列函数的导数:y=f(x²)和v=f(sin²x)+f(cos²x) f(x,y)=arctan(xy),则fx=(1,1)=? 设u=f( lnxy ,sin(xy) ),求x和y关于u的偏导数 设f(x,y)=xe^y+xy,则f(x+y,x-y)=