Find the gradient of f(x,y)=ln(x2+y2)f(x, y) = \ln(x^2 + y^2)f(x,y)=ln(x2+y2).
⟨2xx2+y2,2yx2+y2⟩\langle \frac{2x}{x^2+y^2}, \frac{2y}{x^2+y^2} \rangle⟨x2+y22x,x2+y22y⟩
⟨1x2+y2,1x2+y2⟩\langle \frac{1}{x^2+y^2}, \frac{1}{x^2+y^2} \rangle⟨x2+y21,x2+y21⟩
⟨xx2+y2,yx2+y2⟩\langle \frac{x}{x^2+y^2}, \frac{y}{x^2+y^2} \rangle⟨x2+y2x,x2+y2y⟩
⟨2x,2y⟩\langle 2x, 2y \rangle⟨2x,2y⟩