Recent content by Virtate

  1. V

    How Do You Prove A Closure Equals A Union Boundary A?

    How do you do this proof? Isn't it already obvious given the definition? I have no idea how to go about writing it down. :confused: If someone could help me with this, I would really appreciate it. Thanks :) Sorry I had to write it in such a messy way. Define the closure of A as A closure =...
  2. V

    Finding out if 2003^2004 - 2005 is divisible by 10?

    Thanks Tom!
  3. V

    Modulo, congruences and primes - the love story

    No, I haven't... How does that one work?
  4. V

    Modulo, congruences and primes - the love story

    Can somebody please give me a hint as to how to do the following proof please? I have no idea what to use or where to start :( Suppose that p is a prime and a is an integer which is not divisible by p. Prove that there exists an integer b such that ba is congruent to 1 mod p^2. Thank you. T
  5. V

    Finding out if 2003^2004 - 2005 is divisible by 10?

    I only got as far as 2003 = 3 (mod 10), and I have no idea where to go from there. I think I'm headed in the wrong direction... If someone could give me a few pointers, that would be great.
  6. V

    Finding out if 2003^2004 - 2005 is divisible by 10?

    Hello, I was wondering, how does one go finding out if 2003^2004 - 2005 is divisible by 10? Or that 3^102 * 7^29 is divisible by 33? If someone could help me, I would really appreciate it. Thank You.