Math Homework #1

 

This homework assignment is due Wednesday, October 5th by 4 p.m., either to me in my office or else in our Homework Box.  You may speak to your classmates and others (and me J) about these problems, but your write-up should be your own.  Show your work!

 

Consider the region in the first quadrant bounded by y=4-x2 and y=-2x+4.  Revolve this region about the y-axis.  Compute its volume twice, once integrating with respect to x and once integrating with respect to y. 

 

Do the following problems from Schaum, pp. 287-288:

            15,  18,  20,  23,  24

 

Consider the region in the first quadrant bounded by the x-axis, the curve y=ln(x), and the vertical line x=e2.  Revolve this region about the y-axis.  Compute the resulting volume.

 

There are infinitely many hotels, and they are numbered as … -3, -2, -1, 0, 1, 2, 3, … .  Each of these hotels has infinitely many rooms, which are also numbered by … -3, -2, -1, 0, 1, 2, 3, … .  There are infinitely many guests who need rooms; they are numbered 1, 2, 3, … .  Describe a scheme that will assign each guest to her/his own room, in such a way that every room is filled.