来自郭治的问题
偏导数定义求偏导设f(x,y)=(x^2+2y^2)/(x+y)根据偏导数定义求fx(0,0)fy(0,0)
偏导数定义求偏导
设f(x,y)=(x^2+2y^2)/(x+y)根据偏导数定义求fx(0,0)fy(0,0)
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2020-07-31 23:22
偏导数定义求偏导设f(x,y)=(x^2+2y^2)/(x+y)根据偏导数定义求fx(0,0)fy(0,0)
偏导数定义求偏导
设f(x,y)=(x^2+2y^2)/(x+y)根据偏导数定义求fx(0,0)fy(0,0)
本题要定义f(0,0)比如=0
x趋于0,fx(0,0)=lim[f(x,0)-f(0,0)]/x=limx=0
y趋于0,fy(0,0)=lim[f(0,y)-f(0,0)]/y=lim2y=0