Stewart – Calculus ET 8e Chapter 14 Form F
7. The height of a hill (in feet) is given by
where x is the distance (in miles) east and y is the distance (in miles) north of your cabin. If you are
at a point on the hill 1 mile north and 1 mile east of your cabin, what is the rate of change of the
height of the hill (a) in a northerly direction and (b) in an easterly direction?
8. Find the differential of the function
____ 9. Use the Chain Rule to find
Select the correct answer.
a.
b.
c.
d.
10. The radius of a right circular cone is increasing at a rate of 5 in/s while its height is decreasing at a
rate of 3.6 in/s. At what rate is the volume of the cone changing when the radius is in. and the
height is in.?
11. Use the equation to find .
12. Find equations for the tangent plane and the normal line to the surface with equation
at the point