来源:学生作业帮 编辑:作业帮 分类:数学作业 时间:2024/11/08 09:42:36
(三阶连续偏导数)求大神解答下题并附上详细过程
∂²f/∂x²=y 对x积分得:∂f/∂x=xy+g(y)
∂²f/∂y²=x 对y积分得:∂f/∂y=xy+h(x)
∂²f/(∂x∂y)=x+y,对y积分得:∂f/∂x=xy+y^2/2+h1(x)
∂²f/(∂x∂y)=x+y,对x积分得:∂f/∂y=xy+x^2/2+g1(y)
比较得:∂f/∂x=xy+y^2/2 ∂f/∂y=xy+x^2/2
f(x,y)=yx^2/2+xy^2/2