Homework should be turned in at the BEGINNING OF CLASS. All problem numbers refer to McCallum's book, the required text for the course. You should write up solutions neatly to all problems, making sure to SHOW ALL YOUR WORK. A nonempty subset will be graded. You are strongly encouraged to work on these problems with other classmates, although the solutions you turn in should be your own work.

**Section 11.6**

Problems: 3, 4, 5, 9, 13-19 all

** Hint: ** For #5, use the t-values t = 0, t = Pi/3, and t = Pi. For each one of these
values, draw a contour diagram in the xy-plane. Choose a few function values and sketch the level curves
in the xy-plane. Your answer should consist of three separate contour plots.
For #13-19 use the catalog of surfaces on page 48. State which surface the equation represents
and say a little bit about the surface (eg. hyperboloid of two sheets centered about the x-axis).

**Section 11.7**

Problems: 1, 2, 5, 8, 9, 11, 12, 15, 16

** Hint: ** For #15 and #16, try picking a few key points in the domain. If the c-value needed to make
the function continuous changes from one point to another, there is no one c-value which makes the function
continuous everywhere.

**Section 12.1**

Problems: 1, 3, 6, 8, 14, 23, 24, 26, 28, 30, 32