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Mathematics
Quick fact
In the standard construction, the integer 0 is defined as the equivalence class of the pair (0,0), and the integer -1 is the equivalence class of (0,1), using a clever rule that treats pairs as differences.
Why this is interesting
You've counted 1, 2, 3... but where does 0 come from? And how do you get -3 when you only have the counting numbers? Surprise: integers are not given—they are built.
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Subjects · study & training · careers
Choose something you are considering. FACTREE will give you a clear picture of what it contains, how its main parts connect and where it could lead.
This private catalogue connects 31 subjects, study routes and careers across six broad areas. Public Maps and learner routes remain off.
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See what programming involves, how its main areas connect, and whether you find the knowledge interesting enough to take it further.
Structuring the Programming Map…
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