Question

1. (25 points) The figure below shows the contour plot of f(x,y)-3 -1 - 2y+y. (Credit for the figure is due to UMich instructors.) 6.00U 6.000 1.5 1.0 0.5 0.0 0.5 1.0 1.5 6.000 2.0-1.5-1.0-0.5 0.0 0.5 1.0 1.5 (a) Find all critical points of f. There should be six. Mark them on the contour plot. (Think, but don't write, about how to guess the critical points from the contour plot.) (b) Find f-,) v(,),and fp()-fy(, y) (c) Try to use the contour plot to predict if each critical points is a local maximum, minimum or saddle point. Use the second derivative test to confirm your predictions. Point (z, ) Type (max/min/saddle) Second derivative test to confirm

Answer 1