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Mathematics
Mathematics
Problem
State which of the following sets are finite or infinite: (i)
{
x
:
x
∈
N
and
(
x
−
1
)
(
x
−
2
)
=
0
}
\{x : x \in \mathbb{N} \text{ and } (x - 1)(x - 2) = 0\}
{
x
:
x
∈
N
and
(
x
−
1
)
(
x
−
2
)
=
0
}
(ii)
{
x
:
x
∈
N
and
x
2
=
4
}
\{x : x \in \mathbb{N} \text{ and } x^2 = 4\}
{
x
:
x
∈
N
and
x
2
=
4
}
(iii)
{
x
:
x
∈
N
and
2
x
−
1
=
0
}
\{x : x \in \mathbb{N} \text{ and } 2x - 1 = 0\}
{
x
:
x
∈
N
and
2
x
−
1
=
0
}
(iv)
{
x
:
x
∈
N
and
x
is prime
}
\{x : x \in \mathbb{N} \text{ and } x \text{ is prime}\}
{
x
:
x
∈
N
and
x
is prime
}
(v)
{
x
:
x
∈
N
and
x
is odd
}
\{x : x \in \mathbb{N} \text{ and } x \text{ is odd}\}
{
x
:
x
∈
N
and
x
is odd
}
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