CMPU-145 Spring, 2019
Homework: Due Tuesday, 2/26.
1. Consider A to be the set of all (living) people. Let R be the relation
on A that is defined by a and b have the same birthday. Show that R is
an equivalence relation on A.
2. Just recently, I was looking at a testcase at work that failed. A file with
the name STATEFULONE had to be found in a table, but STATEFULABC was found
instead. It turns out that only the first 8 characters of the name was
stored in the table. Essentially, these two files had the same name since
the remaining characters were not stored in the table. Let A be the set of
all alphabetic file names (i.e. no numbers, symbols, whitespace).
Let R be the relation on A that is defined by a and b such that the first
8 characters of a are the same as the first 8 characters of b. Show that R
is an equivalence relation.