Find the rate of change of f(x,y)=x2yf(x, y) = x^2 yf(x,y)=x2y at (1,2)(1, 2)(1,2) in the direction of the vector v=⟨−1,1⟩\mathbf{v} = \langle -1, 1 \ranglev=⟨−1,1⟩.
2\sqrt{2}2
222\sqrt{2}22
000
−sqrt2-\\sqrt{2}−sqrt2