In Exercise 4, identify the trace in the plane z = l in each case.
Exercise 4
Name the following quadrics.
(a) 36x2 + 9y2 + 4z2 - 36 = 0
(b) 2x2 + 6y2 - 3z2 = 18
(c) 6x2 - 3y2 - 2z2 - 6 = 0
(d) 9x2 + 4y2 - z2 = 0
(e) 16x2 + y2 = l6z
(f) 7x2 - 3y2 + z = 0
(g) x2 + y2 + z2 = 25