MA2312
Spring 2010
Homework 2
John Iacono
January 28, 2010
Read sections 1.1-1.7.
1. For each of these expressions, tell me in the simplest way possible what
they evaluate to. For example, if the question is 2+2, you should respond
4, and not 1 + 3, 2 + 2, or
√
4. If the expression makes no sense, answer
“Doesn’t make sense.” Some of this is a review of some math you should
know.
(i)
{
1
,
2
,
3
}
=
{
3
,
2
,
1
}
(ii)
|{
1
,
2
,
4
}|
(iii)
∅ ∈ {
1
,
2
,
4
}
(iv) 1
∈ {
1
,
2
,
4
}
(v)
∅ ∈ {
1
,
2
,
4
}
(vi)
{
1
} ∈ {
1
,
2
,
4
}
(vii) 1
⊆ {
1
,
2
,
4
}
(viii)
{
1
} ⊆ {
1
,
2
,
4
}
(ix)
{
a,b,c
} ∪ {
b,d
}
(x)
{
a,b,c
} ∩ {
b,d
}
(xi)
{
a,b,c
} - {
b,d
}
(xii)
{
a,b
} × {
1
,
2
}
(xiii) 2
×
8
(xiv)
{
a,b
} × ∅
(xv)
{
a,b
} × {∅}
(xvi) 2
{
1
}
(Your book writes this as
P
(
{
1
}
))
(xvii) 2
{
1
}
×
2
{
2
}
(xviii) 2
1
1