(Solved): Use the contour diagram for f(x,y) shown below to estimate the directional derivative of f in the ...

Use the contour diagram for $$f(x,y)$$ shown below to estimate the directional derivative of $$f$$ in the direction $$\vec{v}$$ at the point $$\mathrm{P}$$. (a) At the point $$P=(2,2)$$ in the direction $$\vec{v}=\vec{i}$$ , the directional derivative is approximately (b) At the point $$P=(2,3)$$ in the direction $$\vec{v}=?\vec{j}$$, the directional derivative is approximately (c) At the point $$P=(4,1)$$ in the direction $$\vec{v}=(\vec{i}+\vec{j})/\sqrt{2}$$, the directional derivative is approximately (d) At the point $$P=(3,0)$$ in the direction $$\vec{v}=?\vec{i}$$, the directional derivative is approximately