Show that the given relation R is an equivalence relation on set
S. Then describe the equivalence class containing the given element
z in S, and determine the number of distinct equivalence classes of
R.
Let S be the set of all possible strings of 3 or 4 letters, let
z = ABCD and define x R y to mean that x has the same first letter
as y and also the same third letter as y.
Determine whether the given relation is an equivalence relation
on the set. Describe the partition arising from each equivalence
relation. (c) (x1,y1)R(x2,y2) in R×R if x1∗y2 = x2∗y1.
Let X be a finite set. Describe the equivalence relation having
the greatest number of distinct equivalence classes, and the one
with the smallest number of equivalence classes.
select the relation that is an equivalence relation. THe domain
set is (1,2,3,4).
a. (1,4)(4,1),(2,2)(3,3)
b. (1,4) (4,1)(1,3)(3,1)(2,2)
c. (1,4)(4,1)(1,1)(2,2)(3,3)(4,4)
d. (1,4)(4,1)(1,3)(3,1)(1,1)(2,2)(3,3)(4.4)
2. Recall that the set Q of rational numbers consists of
equivalence classes of elements of Z × Z\{0} under the equivalence
relation R defined by: (a, b)R(c, d) ⇐⇒ ad = bc. We write [a, b]
for the equivalence class of the element (a, b). Using this setup,
do the following problems: 2A. Show that the following definition
of multiplication of elements of Q makes sense (i.e. is
“well-defined”): [a, b] · [r, s] = [ar, bs]. (Recall this...