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\leftline{Mathematics 241 -- Multivariable Calculus}
\leftline{Quiz 6 -- October 25, 2013}
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\leftline{Your Name: $\underline{\ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ \ }$}
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Let $f(x,y) = \sin(x) - \sin(y)$.
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A) (10) Find all critical points of $f$ in the rectangle $[0,2\pi] \times [0,2\pi]$.  

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B) (10) Here is the gradient vector field of this $f(x,y)$ plotted on the same rectangle.
Classify each critical point as a local maximum, a local minimum, or a saddle point.  
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