A9.1.10设 (x,y)=(x)^2+(y)^2+sin xy, 在点(1,1)处求d f.

设区域 :(x)^2+(y)^2leqslant 1, 计算 =(iint )_(D)[ sin (x)^2cos (y)^2+sin (x-y)dxdy]

设函数y=f(x)由方程xy+2ln x=y4所确定,求曲线y=f(x)在点(1,1)处的切线方程.设函数y=f(x)由方程xy+2ln x=y4所确定,求曲线

7.求下列函数在指定点处的泰勒公式:-|||-(1) (x,y)=sin ((x)^2+(y)^2) 在点(0,0)(到二阶为止);-|||-(2) (x,y)

1.函数 (x+y,xy)=(x)^2+(y)^2-xy, 则 f(x,y)=

设 (x,y)=dfrac ({x)^2+(y)^2}({e)^xy+xysqrt ({x)^2+(y)^2}} ,则 (f)_(x)(1,0)= __ _.

164 设f(x,y)有二阶连续偏导数, (x,y)=f((e)^xy,(x)^2+(y)^2), 且 f(x,y)=1-x-y+-|||-(sqrt ({(x

设 f(x,y)= sin dfrac (1)({x)^2+(y)^2} , ^2+(y)^2neq 0,-|||-0, ^2+(y)^2=0,-|||-考察函

函数f(x,y)= dfrac (xy)({x)^2+(y)^2},(x)^2+(y)^2neq 0-|||-0, ^2+(y)^2=0在点（0，0）处（）。

1.设 sin y+(e)^x-x(y)^2=0, 求 dfrac (dy)(dx).-|||-2.设 ln sqrt ({x)^2+(y)^2}=arctan

求旋转曲面=(x)^2+(y)^2在点=(x)^2+(y)^2处的法线方程A.=(x)^2+(y)^2B.=(x)^2+(y)^2C.=(x)^2+(y)^2D