Prove the following Theorems:
1. A finite union of compact sets is compact.
2. Any intersection of compact set is compact.
3. A closed subset of a compact set is compact.
4. Every finite set in IRn is compact.
Prove the following statements!
1. If A and B are sets then
(a) |A ∪ B| = |A| + |B| − |A ∩ B| and
(b) |A × B| = |A||B|.
2. If the function f : A→B is
(a) injective then |A| ≤ |B|.
(b) surjective then |A| ≥ |B|.
3. For each part below, there is a function f : R→R that is
(a) injective and surjective.
(b) injective but not surjective.
(c) surjective but not injective.
(d)...
Unless otherwise noted, all sets in this module are finite.
Prove the following statements...
1. If A and B are sets then (a) |A ∪ B| = |A| + |B| − |A ∩ B|
and (b) |A × B| = |A||B|.
2. If the function f : A→B is (a) injective then |A| ≤ |B|. (b)
surjective then |A| ≥ |B|.
3. For each part below, there is a function f : R→R that is (a)
injective and surjective. (b)...
Averages and variation
Consider two data sets A and B. The sets are identical except
the high value of the data set B is three times greater than the
high value of data set A.
(a) How does the median of the two data sets compare?
(b) How do the means of the two data sets compare?
(c) How do the standard deviations of the two data sets
compare?
(d) How do the box- and –whisker plots of the two...
A student suggests that for any two sets A and B: Statement 1:
AUB' = (B/A)' Statment 2: AUB' will never contain an element in set
B Is each of these statements correct or incorrect? Use and example
or visual representation in your explanation please.
Unless otherwise noted, all sets in this module are finite.
Prove the following statements...
1. Let S = {0, 1, . . . , 23} and define f : Z→S by f(k) = r
when 24|(k−r). If g : S→S is defined by (a) g(m) = f(7m) then g is
injective and (b) g(m) = f(15m) then g is not injective.
2. Let f : A→B and g : B→C be injective. Then g ◦f : A→C is
injective.
3....