Пожалуйста помогите решить. 11.5.43.
∂u/∂x=(x)`*ln(xy)+x*(ln(xy))`_(x)=ln(xy)+x*(1/(xy))*(xy)`_(x) =ln(xy)+(xy)/(xy)=ln(xy) ∂^2u/∂x^2=(ln(xy))`_(x)=(1/(xy)) * (xy)`_(x)=(y/xy)=1/x ∂^3u/∂x^2∂y =(1/x)`_(y)=0 ∂u/∂y=x*(1/xy)*(xy)`_(y)=x^2/xy=x/y ∂^2u/∂y∂x=(x/y)`_(x)=(1/y) ∂^3u/ ∂y∂x^2=(1/y)`_(x)=0