Math 424 A and 574 A, Autumn 2012

Homework assignments

All problems are from Apostol (unless explicitely stated otherwise)


 

Turn in:             1.4, 1.6, 1.14, 1.15, 1.16, 1.21

 

Do NOT turn in (but make sure that you know how to do them!):

                        1.2, 1.3, 1.9, 1.11, 1.19, 1.22

                        Prove that the set F(p), with addition and multiplication defined mod p, is a field if and only if p is a prime.

Due date:  Monday, October 8




Turn in:             1.25, 1.26, 1.32, 1.34, 2.7, 2.12, 2.13, 2.15, 2.20

 

Do NOT turn in :  1.23, 1.24, 1.27, 1.29, 2.5, 2.6     

Due date:  Wednesday, October 17



Turn in:            3.4, 3.10, 3.11, 3.13, 3.29, 3.31, 3.32

                        (do 3.10-13 in general metric spaces, not just R^n)


                        Prove that the distance function d(f,g) = sup {|f(x)-g(x)|, x in X}
                        is a metric on the space of bounded functions f : X -> R. Show

                        that the set {f, |f(x)|<1 for all x in X} is open if and only if X is finite.

 

                        Prove that the Cantor middle third set is closed and uncountable.

                       

Do NOT turn in:  3.2, 3.3

 

Due date:  Friday, October 26



Turn in:                        3.5, 3.6, 3.24, 3.25, 3.47,  3.48, 3.52

 

                        Prove that the Cantor middle third set is perfect (see exercise 3.25).

 

Due date:  Wednesday, November 7

 


Turn in:                        3.16, 3.33, 3.34, 3.39, 3.40, 3.41, 3.42

 

Do NOT turn in:  Prove that a metric space in which every infinite subset has a limit point is compact:

First prove that such a space is separable (see exercise 3.32; to prove this, show that
for each n there are finitely many points  x(j)=x(j,n) such that every point is within distance

1/n from one of these x(j,n)). Then use 3.34.

 

Due date:  Friday, November 16

 


 

Turn in:                        4.2, 4.3, 4.10, 4.11a,b,c, 4.14, 4.15

 

Do NOT turn in:  4.1, 4.7, 4.8

 

Due date:  Wednesday, November 28


 

Turn in:                        4.16, 4.18, 4.23, 4.25, 4.30, 4.34, 4.38, 4.39 

 

Due date:  Wednesday, December 5