Subset Math Example 3

Follow the full solution, then compare it with the other examples linked below.

easy

Let

X = \{1, 2, 3\}

and

Y = \{1, 2, 3, 4, 5\}

. Is

X \subseteq Y

? Is

Y \subseteq X

Answer

X \subseteq Y \text{ and } Y \not\subseteq X

Subset relationships are not always symmetric.

X \subseteq Y

does not imply

Y \subseteq X

unless

X = Y

About Subset

Set $A$ is a subset of set $B$ if every element of $A$ is also an element of $B$ , written $A \subseteq B$ .

Let [formula] and [formula]. Determine whether [formula].

List all subsets of [formula].

Let [formula] and [formula]. Is [formula]? Is [formula]?