Answer Happy

Preview Activity 20.1. In Investigation 19, we studied the set of symmetries of an object under the operation of function composition. Compare and contrast this set to each of the following sets with the given operation. Which properties do they share, and which do they not share? (a) Z, the set of integers under addition (b) E, the set of even integers under addition (c) Q. the set of rational numbers under addition (d) R7, the set of all positive real numbers under multiplication (e) Zn, the set of all congruence classes of integers modulo n under addition (0) {-1,1}, the two element subset of the integers under integer multiplication (g) Mnxn(R), the set of n x n matrices with real entries under addition