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Addition in R

  1. Mar 2, 2008 #1
    1. Consider the set Z of integers, and let R denote the subset all multiples of 4. Define addition as ordinary addition in Z, and define multiplication * in R by a*b = ab/4

    a. Show that (R, +, *) is a ring with unity (what is the unity of R?)

    b. Show that the mapping Ø: R → Z defined by Ø(x) = x/4 is an isomorphism
  2. jcsd
  3. Mar 2, 2008 #2


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    That looks straightforward enough. Why don't you just prove those things? What's stopping you?
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