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Introductory exercise about set equality
", "licence": "Creative Commons Attribution-ShareAlike 4.0 International"}, "statement": "Consider the three individual elements $1, 1$ and $2$. If we consider these elements as a single unordered collection of distinct objects then we call it the set $\\left\\{1,1,2\\right\\}$. Because sets are unordered this is the same as $\\left\\{2,1,1\\right\\}$ and because we only collect distinct objects this is also the same as $\\left\\{1,2\\right\\}$.
\nFor example, let $A=\\left\\{\\var{A[0]},\\var{A[1]},\\var{A[2]},\\var{A[3]}\\right\\}, B=\\left\\{\\var{B[0]},\\var{B[1]},\\var{B[2]},\\var{B[3]},\\var{B[4]}\\right\\}$ and $C=\\left\\{\\var{C[0]},\\var{C[1]},\\var{C[2]},\\var{C[3]},\\var{C[4]},\\var{C[5]}\\right\\}$.
", "advice": "You can check to see if $A \\subset B$ by progressively checking if each element of $A$ is also in $B$. There are six questions so you will have to do this six times.
\nThe second part of this question builds on the first. You just need to look at your answers and find the sets which contain each other. It is a bit like the 'less than or equal to' relation in the sense that if you have two numbers $x$ and $y$ where $x \\leq y$ and $y\\leq x$, then it must be true that $x=y$.
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